Large Tank IN a Basement-Ventilation Suggestoin Please oh brethern of the mamoth tank

[skippyreef]

SO the title says it all!!

The main tank is 72*36*24 and has a total volume of 270 us gallons. The sump will likely be 125 gallon tank and I have a 40 gallon custom frag tank as well.

I am looking at around 435 gallons of water plus a resovoir for topping off the tank (figure 30 gallons) so 465 gallons in the basement minus air space for the sump so take it back down to about 435 gallons :)

I have two glass block windows in the basement. I also live in SE Michigan as well so we have winter here LOL

The basement has a fresh air intake that feeds right at the furnace.

I have no problem installing fans to vent to the outside I can just drill through because the side of the house are sided with vinyl siding.

My questions are how many fans and where?

The tank will be two sides viewabel (I have the tank in the basenment and we are starting to finish the basement now) with a maintenece room for reefing activities behind it. I am using greenboard 5/8 and styro insulation around the tank to decerase noise.

would it be better to vent the hood directly to the outside or vent the room its in or both? I also wondered if another fan on the opposite side of the basement to circulate as much air as possible?

Please suggest, provide links, experience, drawing, tarot card readings, LOL ect.........

Thanks in advance!!!

[szwab]

Mantis here on RC has a nice system that turns on by either temp or humidity and uses a furnace type blower. I'll send him a link to this thread.

[OldmillXxX]

I too would like some additional information on this. I have a 55g upstairs with a 70g stocktank in the rock wall basement. I have a window fan, on low in the room upstairs that gently sucks the air out of the room (it stays quite cool for now with the central AC running). I still; however, get substantial humidity in the basement and condensation on the air ducts and furnace in the basement. The damp air makes the AC run more and harder, not to mention the bad air created in the basement that gets dispersed to the rest of the house. Needless to say, I am in the process of redoing everything to prevent these measures.

I thought about building a small room in the basement to vent outside, or purchasing one of those plastic storage sheds like you see in the stores and modifying that (with venting) to contain the moisture better.

Like most on heare, I'm trying to take the cheapest approach I can. One thing I have learned is that cheaper usually means longer and more headaches to get the same results.

Good luck! I'm listening...

[Mantis]

I have a large tank (400 gallon) upstairs and a tank room in the basement.
The upstairs right now is 40% humidity. The tank room stays at 60%.

An exhaust fan will turn on if the basement tank room gets to be above 74 degrees or a humidity level of 60% or above. This is controlled by an Air 1 controller. I also run a dehumidifer in another part of the basement so when the exhaust fan kicks on it draws less humid air into the tank room
http://www.plantlightinghydroponics.com/product_info.php?cPath=370_363&products_id=361

I'm using one of these fans
http://www.energyfederation.org/consumer/default.php/cPath/30_85_99

With my currrent system I'm able to keep my water temp. below 79 degrees without the use of a chiller.

[skippyreef]

Mantis,

Which Model Fan are you using? I was planning on using a few to vent teh tank room and basement. With 400 gallons of water in the basement I want to make sure to exhaust properly. Do you have pics of the system?

[springerhd]

Looking to do something similar for my fish room which is in my garage. Where do you vent the exhausted air to?

[Mantis]

I'm using the 190 cfm model, just depends on the size of the room your trying to vent. The nice thing about these fans is they have a damper built in so it shuts out outside air when not running.

It exhausts outside the house through a 4 inch hole with a dryer vent cover

[skippyreef]

From what I have read I should try to seal the fish room up as best as I can but there are always gaps in an inwall design and spaces for air to escape.

I will be using green board and a water proof paint (marine grade for floor and ceiling in this area. I am estimating the room will be
9x10 or 90 Sqft.

I ahve read about teh negative pressure situation in houses with appliances (heaters/water tanks) drawing in CO and it is scarey.

I have monitors BTW (I am a dad LOL) for this. But I do not want to take chances either.

The house is new (built in 2004) and we are the original owners. I took pictures of the area where the tank will be. There is a furnace vent that is going to be in the tank room for A/C and Heat. The house is 1660 SQ ft two story with a 3 ton A/C unit. We slightly oversized it D/T upper floor cooling. It takes out humidity well.

The furnace has a fresh air intake that feeds it with fresh air via a 6 inch pipe as well as another route for make up air via a 6 inch pipe. I will post pics of all this now. Please advise on what you think are the best measures to mold proof this area of the house!!! The Exhaust fan in the fish room is a must but any thing else you other large tank guys have done is appreciated so please share!!

Area to be enclosed (rest of basement is also being finished.
http://img.photobucket.com/albums/v240/skippyreef/Picture023.jpg





Furnace (which will be in a seperate utility room) the black pipe leading into the galvanized cylinder is the other air flow to the furnace. I think this is to prevent negative pressure but would like opinions.
http://img.photobucket.com/albums/v240/skippyreef/Picture024.jpg

Heat vent
http://img.photobucket.com/albums/v240/skippyreef/Picture025.jpg

Small window in tank room area
http://img.photobucket.com/albums/v240/skippyreef/Picture026.jpg

ANother shot of tank room area
http://img.photobucket.com/albums/v240/skippyreef/Picture027.jpg

Cold air make up for house (we have two lines like this, both to the furnace, the other is the one that feeds outside the furnace)

http://img.photobucket.com/albums/v240/skippyreef/Picture028.jpg

I appreciate any input! I want to do it right the first time!!!

[skippyreef]

Mantis,

Do you have any issues with negative pressure?

[LargeAngels]

Just keep in mind that anything metal in the room will eventually rust. May not show up the first year or two, but it will. I would suggest a good rust preventative primer for anything that will be metal. My first house I didn't think about that so much, but with a total volume of 1,000 gallons after a few years you start to see it.

[skippyreef]

does that mean the pump too ? Not to much metal. I will take teat vent off though and maybe just get a plastic one with a damper on it to prevent backflow into the ventilatiopn system.

[capncapo]

A simple suggestion for those of you with humidity issues in the basement:

Cut a hole in your cold air return that is the size of a register. Place the register in the hole and put two screws in to hold the register. Open the register and let it suck your warm humid air into the return.

The air will become part of your heating / cooling air and will therefore be dehumidified as it passes through your system.

I have done this on two systems with excellent results. They have gone from condensate dripping off of supply runs to having a small amount of sweat. The good thing is that it costs practically nothing, takes very little time to do, and, you can do it yourself.

For those of you with vent fans:

Remember that in order to exhaust air from your house/basement, you have to be sucking outside air in from somewhere. If you live in a humid area your are trading cooler, humid air for fresh, hot humid air so you are doing nothing but costing yourself money to cool and dehumidify the warm air.

Conversely, in winter you are sucking in dry air ( a good thing ) but it is cold air and you now have to pay to heat that air. There is a device called an "air exchanger" that will exause your humid air and bring in dry air but it will also retain 80% of the heat that would otherwise be lost. They are great for the winter but obviously not summer.

Humidity does NOT make an A/C work harder or longer. Your A/C runs until it satisfies the thermostat and then shuts off.

Most furnaces that have a fresh air intake that is piped from the outside are 90% efficient units and the intake is part of the system that allows them to achieve that efficiency.Those units also have an exhaust run that is piped to the outside versus just letting it go up a flue. Those furnaces also create a condensate while running that is very acidic and will dissolve any metal plumbing pipes that it drips into. There is a neutralizer that is made that plugs into the condensate line to neutralize the acid in the condensate. If you have metal drain pipes in your floor drain, I would highly recommend that a neutralizer be part of your system.

[skippyreef]

The cold air return is the portion where that ancilaary pipe is correct in the pics above. So the wamer humid air will be circulated into the furnace and teh humidity is removed in both winter and summer this way?

[skippyreef]

Also, will the salt linger on the air that is sucked into the cold air intake and rust the heat exchanger over time? The furnace is being seperated in a utility room so as not to come into contact with the tank and the tank will be in its own room as well (in wall) with a viewing area outside the fishroom (classic 2 sides viewable in wall).

[capncapo]

skippyreef,

The cold air return is the side of your furnace where the filter resides. All of the duct work leading to that side of your furnace is part of the return. You can place the register anywhere in that run. The closer to the ceiling, the better.

In summer that air will be dehumidified by being blown through your A coil and in winter it will be vaporized and will go out your flue ( or exhaust for 90% units ).

Unless you are sucking salt "spray" into the return there is no need to worry about your heat exchanger. Don't forget, when water evaporates, the salt stays behind hence the need to top off with plain RO/DI water.

Something you can do if space and ceiling height permit is to have a piece of duct run into your fish room that would be tied into your cold air return.

[skippyreef]

so the duct running into the cold air return from the fish room will exhaust out the stale air in there and vaporize it as you have said up into the flue and out.

I think I would rather do it this way and I have the room. I will incorporate that into the design. Will doing it this way take care of any humidity I would have? I also have a vent on the side of the furnace from the unit itself that blow out cool air from the furnace or warm air when it is on and this is not closeable. It is not a standard floor or wall ven it is skinnier than those and a tad longer. Will this interefer with things?

[ReeferMac]

I've got a 230 gallon in the basement, and have heat/humidity issue's all summer long. Capncapo's got some good advice, I'll have to re-read in more detail and see if I can implement. Those glass block windows look great, but are a PIA for venting (I have similar ones). As you're doing this all from scratch, I'd suggest taking your time and doing it all right, the first time. Well worth the money and aggrevation, in the long run.

- Mac

[griss]

Mac, I'm with you. I have about 850 system gallons in my basement. I have a exhaust fan on a humidistat for the winters (no sense in using that in the summer as it will pull in 90% humid air), a dehumidifier running full time and a window AC unit running 24/7. With all this, I still hit 60-70% humidity in the basement:(

Our Furnace / AC does not have any return ducts in the basement. So, I am making Capncapo come over Sunday and help me put one in:D

[skippyreef]

I have two return ducts in the basement and one is right in the tank room area from my furnace. If it is really this simple (and I dont doubt you at all) I wonder why people havent thought of this? Is it becasue we are not HVAC guys LOL :)

SO anywhere along those cold air runs I can tap into them and pull in the basement air to have it exhuast out. Another thing Is I am putting in a dutch door on hte basement itself and using the full door on the fishroom. We never leave teh door closed to the basement any way. Will leaving this door open assist with pulling in air from the rest of my house to be circulated and mitigate the humiduty as well?

I am going to go with a 100 gallon sump now that will have about 60 gallons of water in it and the tank should have around 350 gallons in it. this is a slight reduction in volume LOL. If I need a dehumidifier I found some that are reated to run in a basement environment that are areound 230.00.

By doing this though I should be ok is what you are saying it seems. Keep the opinions and experiences coming.

[Johnsteph10]

griss - is your canopy open or closed?

My aim is to have the canopy closed and relatively air tight along with the fishroom so that I can "separate" the rest of the basement from the fishroom and the tank.

Does anyone do this? I'm hoping it should make things easier to control.

[griss]

Skippy,

I actually directed Capncapo to this thread after a discussion we were having this AM. He's done this to Nanook's returns and according to Nanook, it is working like a charm. Capncapo has also done it to another local reefers and it is working there as well. He's coming over to my house this weekend to help with mine.

Capncapo told me that it is best to cut a hole in the return duct as high up as possible. If you already have return vents in your basement, it may not help. In Nanook's case (and mine too) our basements have return ducts, but they do not have vents in the basement. By cutting a vent into it, we are now pulling air from the basement where no air was pulled before. The air then passes over the condenser in the AC unit. This allows the moisture to condense and be removed by your AC.

[griss]

Originally posted by Johnsteph10
griss - is your canopy open or closed?

My aim is to have the canopy closed and relatively air tight along with the fishroom so that I can "separate" the rest of the basement from the fishroom and the tank.

Does anyone do this? I'm hoping it should make things easier to control.
John, right now my basement is not finished. Just a few walls away from the tank are up. So, no hood, no walls around the tank. In this pic, you can see there is no canopy or any type of enclosure around the system as it is today. Note: The date on the picture is incorrect.

http://reefcentral.com/gallery/data/1/423Tank2-med.jpg

[griss]

Latest picture I have is from November (date on the camera is wrong):rolleye1: and I'm not a good photographer. You can see, still no hood or canopy here.

http://reefcentral.com/gallery/data/503/423Tank4-med.jpg

[skippyreef]

Griss,

What I meant by returns is heat registers to heat and cool the basement not actual intakes LOL. I am going to call a friend who is a HVAC guy here and discuss getting this done this weekend.

[skippyreef]

I just went down to look and the large black intake (flex hose that feeds the cold air intake manifold (dont know if right word) comes in through the proposed fish room. Would I want to open up and vent in that or just go into the sheet metal and run a 6 inch diameter feed into the manifold from the fish room / tank area?

Also would it be wise to do a run from the opposite end of the basement as well or is one feed into the return enough?

[capncapo]

Will doing it this way take care of any humidity I would have? I also have a vent on the side of the furnace from the unit itself that blow out cool air from the furnace or warm air when it is on and this is not closeable. It is not a standard floor or wall ven it is skinnier than those and a tad longer. Will this interefer with things?

Taking care of humidity is the whole reason for doing this.

Your vent will not interfere with this. What it will do is "mix up" the air in that particular room and should keep temperatures and humidity levels relatively even throughout that room.

[capncapo]

I just went down to look and the large black intake (flex hose that feeds the cold air intake manifold (dont know if right word) comes in through the proposed fish room. Would I want to open up and vent in that or just go into the sheet metal and run a 6 inch diameter feed into the manifold from the fish room / tank area?

Also would it be wise to do a run from the opposite end of the basement as well or is one feed into the return enough?

You want to open the sheet metal ( provided that it is, in fact, part of the cold air return ). Don't touch the cold air intake.

I don't think that it will be necesssary to put a second register at the other end of the house but if that end should remain humid for some reason, a second register couldn't hurt. After all, if you don't like what it does when you add it, just close it. No harm done.

Something that I have told my "guinea pigs" is that you will be doing nothing that will hurt anything or can not be reversed so feel free to "experiment" if the mood strikes you.

[skippyreef]

Well I do appreciate this advice. I called several places in my area about installing an HRV unit and the price was a consistant 1400-1600 dollars for a unit.

I did see one on a website for 459.00 today. I guess If I can do this and its simple then simple is good!

And I also believe the actual volume will be closer to 350 and I only have another 50 gallon tank up stairs so I will likely not have the humidity difficulties like people with more water than I have :)

[Whaledriver]

I am still looking for a varible speed fan controler to operate a 350-450 cfm fan. I am planning to run air into and out of the tank hoods with ductwork that is connected to the outside. I could at a later point add a air to air exchanger to use the heat in the winter.

Most setups for multiple tanks are simple to set up but to operate the automaticly and efficiently is a problem. The HVAC industry is the place to look but you need to be an expert to find the right electronics. I can find controllers to monitor heat and humidity but they dont change speed, they just go on and off. I want to find one that will also control a variable speed fan that increases speed as the temperature rises. The best option so far is to get a 3 speed fan or multiple fans that go on at differant temperatures.

[ReeferMac]

Could you hook up an aquacontroller? I'll betcha the dimable X10 modules would work?

- Mac

[skippyreef]

I ordered a 290 CFM fan for the room. I also am looking into a split A/C unit as a possibility. My buddy will install it for very little.

A freind here is coming over and we will install the fan to a 6 inch duct to the outside. We are sealing the room off from the rest of the basement. But we are placing dampered vents near the bottom of the wall that lead into the fishroom. When the fan kicks on to exhaust the humid air it will draw in colder dry air from the basement and the makeup air will replenish the air moved into the room.

I am also cutting a vent hole into the cold air return line to draw in air from the basement to pull out humidity in the winter and summer.

I will not have 4K or even 2K like Mr 4000 or Aquariumobsessed but I dont want a moldly basement and house either!

[capncapo]

Skippy,

Make sure that your furnace room is not sealed off from the rest of the basement otherwise your make-up air will not be coming from that room. If it is, you will need to add a vent to the furnace room to allow the make-up air out of the room.

[skippyreef]

I am going to vent it to allow that so I dont get teh negative pressure thing. Then again if the room is sealed the negative pressure will not happen anyway right?

[capncapo]

It should not happen with the make-up air coming in from outside and going into the furnace room.

[skippyreef]

This is way moer involved than I ever thought it would be LOL but its a learning experience for sure.

[Whaledriver]

Could you hook up an aquacontroller? I'll betcha the dimable X10 modules would work?

- Mac

I will look into that next week. I have never used a controller. Could it change the fan speed based on teperature?

[ReeferMac]

Originally posted by Whaledriver
I will look into that next week. I have never used a controller. Could it change the fan speed based on teperature?

That one I'm not sure on. I know people that use the dimmable X10's to control moonlights made up of LEDs... If you throw a resistor in there, you can use the AQ and X10 module to simulate phases of the moon. The AQ is programable, you just have to have enough 'steps' in the dimmer module, for the desired effect. In the case of controlling fans, you could have voltage set-points for the fans, based on the temp of the tank? Temp=90, fan/X10 voltage = .... etc.

- Mac

[beerman0831]

I also have done this for a few people and they had nothing but positive results.But then again I knew that it would work.Everything that capncapo is saying is true.Nothing that you do will harm anything so just experiment till you get the temp and humidity to where you want them.



Ken

[skippyreef]

I am going to get some side cutters and a vent this week and just go for it!@!!

[capncapo]

Some right hand and left hand snips would be easier but have at it. You might want to contact griss and see what he says about his humidity level. We worked on his this weekend.

A note for anyone who does this:

Don't expect everything to be better overnight. It takes a while for all of the residual dampness to "leach" out of the floor joists and anything else that is capable of absorbing moisture from the air.

Typically, as long as the A/C is running there will be a noticeable drop in humidity. At night when the A/C doesn't run too much, the air will get humid again from evaporation AND from residual moisture.

After a week or two, the basement has had enough time to dry out significantly and the humidity level remains fairly low overnight.

Also, be careful when cutting the duct work. If you get cut by the tin it will typically bleed like crazy for a short time. Don't know why but it must be something in the galvanizing process that acts like an anti-coagulant. I'm not saying it is a dangerous cut that needs medical attention; it just bleeds a bit and can look like a murder scene.

[skippyreef]

Capncapo,

I will get the correct tools as you suggest. The cool thing is my basement is dry as a bone right now! LOL SO there is no moisture in it from anything.

I went around the house and checked all the gutters, assessed the grade for drainage, tested the sump pump, and I am going to wrap the pipes to prevent condensation on them as well.

I am placing the vent in the cold air return that will be in the viewing room. the furnace room is adjacent to it so the make up air will come from vents between the room as you suggested earlier in the thread. I am sealing off the utility room from the viewing room and the viewing room from teh rest of teh basement. I am feeling much better about this entire process now and think that with a dehumidifier in the viweing room, the fan, and your resolution all will be good!!

[griss]

As Capncapo mentioned, we did this modification to my AC this weekend. Within a couple hours the humidity had dropped quite a bit 5-10% in the basement. However, as evening set in and the AC wasn't running as much, the humidity creeped back up. But (as Capncape mentioned) this was expected and over time, the wood and other items that absorb moisture will dry out. So far, I give a big :thumbsup: to this modification.

[skippyreef]

post pics of teh Mod please so I have someting to copy LOL

[griss]

Originally posted by skippyreef
post pics of teh Mod please so I have someting to copy LOL
I'll try to remember to take and post some pics tonight.

[skippyreef]

Griss,

how many opening did you make? and were the openings very near teh tank itself? Mine will be in the viewing room with the tank. the utility room behind it will have that one way air flow fan and draw in air from the viewing room which is supplied by the make up air in the furnace room via vents between the rooms themselves.

[griss]

Right now my basement isn't finished. So, we just put one vent in about 4 feet from the tank.

[skippyreef]

and that one vent is to intake the air through the cold air return into the the condensor / furnace to dry it out correct?

[griss]

Originally posted by skippyreef
and that one vent is to intake the air through the cold air return into the the condensor / furnace to dry it out correct?
Yep.

[skippyreef]

Thanks Gris,

Looking forward to a pic or two to give me some prespectives on this little house saver!

[szwab]

capncapo:
just to make sure will this effect the heating/cooling of the rest of the house in any way? Mainly in the efficiency dept. I've thought about doing this for a while now, but Know zero about HVAC so this has been very helpful.

thanks

[capncapo]

So far there have been only possitive results. The rest of the homes have had no noticeable changes.

Be advised that I have not had any of the homes with the mod go through the winter yet. My guess on this is that the upstairs parts of the home will be more humid than they used to be BUT most homes can stand more humidity in winter. Most of them are far too dry in winter AND added humidity should allow for a reduced thermostat setting due to the fact that humid air "feels" warmer that dry air. Some, but not all, of the humidity will be exhausted up the flue.

If the house is too humid in winter there are a number of cost effective ways to reduce it but during the summer, the choices are very limited. This works as good or better than any of the choices that I have seen people try.

Dehumifiers help but produce a ton of heat and are somewhat costly to operate as they are nothing but a small air conditioner without the benefit of removing heat. If you live in a dry area, vent fans work good but where I live, a vent fan would make matters worse. You can always run a window air conditioning unit downstairs if you have windows but the expense is cost prohhibitive. This is a good way of alleviating humidity without having to go through a great deal of work or expense.

[szwab]

you've got me sold off the Lowe's tomorrow. I'll post the results in a week or so. thanks for the help and advice. I guess worse case in the winter I could close the vent if needed.

[capncapo]

Yep, you can close it or just "dampen" it down a bit to regulate it.

I have a feeling that your area gets fairly cold and that your furnace runs pretty much in winter. If that's the case you may not have to do either as much of the humidity will eventually make it up the flue.

One other benefit to the added humidity in winter is that if you do reduce your thermostat setting, that act in itself will also reduce your evaporation because cooler air can not hold as much moisture as warmer air.

Good luck and definitely keep me informed. I have been wanting to come up with a cure for Ich, a way to eliminate shipping stress and many other things so that I could "give back" something to the hobby. Whoda thunk it would have been this easy.:D

[skippyreef]

Seems that this idea is a good one. I am also interested in the results others are seeing. Again my house is pretty dry but I do live near Ann Arbor, MI and we get some cold snaps in the winter thats a fact. In the summer its the humidity that kills us! I am doing the Mod as well.

What size vent would you recommend before I go off and get teh wrong thing..

[szwab]

good question
I was assuming 5x11 or somewhere in that ball park

[capncapo]

Skippy,

When we did Georges (griss) place this weekend, he had me go to the hardware store with him to choose what we would use. I had him buy the largest register they had that would fit in his return duct. If it's too big you can always close it down but if it's too small you have to buy and install another. I believe that the cost of that register was like $11.00 including tax. Not bad at all.

I would suggest that you have your friend who does the HVAC work give you a couple of 1/4" hex head sheet metal screws and use them to mount the register. The screws that come with them will work but are awfully long for just going into the duct work.

You guys need to remember that this is more-or-less experimental in your particular application. I can tell you what I've done elsewhere but that wasn't done to YOUR house and every house and heating/cooling system is different. By buying a large register you have much more flexibility as to how much air you care to bring into your systems.

[skippyreef]

OK,

thanks for the pointers on this! I will keep you posted as I go through the basement remodel and gettign this thing going. We start framing Next Wednesday.

[capncapo]

Good luck!

[griss]

Originally posted by skippyreef
Thanks Gris,

Looking forward to a pic or two to give me some prespectives on this little house saver!
Sorry, busy night last night. I'll try to take some pics tonight. But we have another busy night with kid's summer activities.

[Mantis]

capncapo, thanks for the idea.

I added this mod. to my system, now my exhaust system will only run when the AC isn't on, when the weather cools a bit.

One question, I usually run the furnace fan all the time, even when the AC and furnace are off because we have a big whole house hepa filter.

Should I not do this any longer because of this mod.?

[capncapo]

Mantis,

Running the fan won't hurt anything to speak of. It may cause your squirrel cage to get some surface rust though IF the paint on it isn't completely covering it.

My biggest concern with doing that would be that you will be taking the basement air and circulating it through the house with no chance of dehumidifying the air until the unit kicks on. You would, in essence, be making the rest of the house as humid as the basement and would need to set your thermostat lower to compensate for the added humidity. It would also most likely increase the evaporation rate of the tank because the air in the basement will become warmer and dryer.

If it were me, I wouldn't do it.

[billpa]

capncapo

I have a question for you. I have double returns in all of my rooms in my house (for winter or summer). I guess you call that a high or medium effiecient system as it recirculates either the hot air and cools it or the cold air and warms it. The duct work runs the length of my basement. Half of the basement is framed out as a laundry room where the gas furnace and AC resides. The other half is where my 180g tank is. Ive been running a dehumidifier but it definitely brings the heat up quite a bit. So Im looking to add one or two vents from my return in the basement. Its behind a wall inside of the laundry room. And its the soft ducting...no pipes. What would be the best way to add a vent? Should I add one in the laundry room and the tank room? And would this design eliminate the need to use a dehumidifier down the road (as you said it takes a little while for things to balance out)

Thanks in advance!

billpa

[capncapo]

I assume by 'soft ducting" that you are referring to "flex-duct"? Flex duct is the "plastic covered slinky surrounded by insulation covered in plastic.

Or are you talking about the "duct board"? The soft "celotex" looking stuff that resembles a bunch of fiber glued together to form a board.

[billpa]

No...its square in shape. Its soft insulation I think...wrapped in the reflective material. Please excuse my ignorance but I know nothing about HVAC. This duct runs 3/4 the lentgh of my basement and then stops. It then looks to go straight up....I think the returns in my rooms are just vents inside of a framed out area. I also have the same soft ductwork for exit from the furnace and the AC. But from that duct, there are metal ducts that are attached and run between joists in my basement and to registers around the house on the first floor. Any ideas?

Thanks!
billpa

[billpa]

I did a little bit of searching and it looks like it is made of duct board (possibly fiberglass...have to check). Does this make sense? Also would it be a problem pulling moist air into it because of the possibility that moisture will be trapped inside and creating a place for mold to grow. Perhaps I can trace the duct back to the furnace and see if there is a place for a better connection.

billpa

[capncapo]

Billpa,

If it's what I'm thinking of, I may have some bad news for you. Does it remind you somewhat of a soft particle board?

If so, that stuff is not on my list of favorites. With the right tools, that stuff almost installs itself. It's light and extremely easy to work with. I checked into buying the tools to install that stuff. I talked to a local supplier about it and was told that I did not want to use it. I spoke to a friend in the business who works for a company that uses it. He told me that I didn't want to use it. Both told me that it is prone to mold and doesn't hold up well to moisture. That would be my guess as to why you have it mainly being used for your returns.

Make sure that your installation is not using it for some type of sound or thermal insulation. If is not used as insulation ( with tin inside ), I can't say that I would really recommend this modification to you. IF the material that you are using is what I'm thinking of, you could be opening a can of worms by performing this modification.

DO NOT take me at my word on this. It has been a while since I looked into this and the materials may have changed/improved in that time.

I would recommend that you find someone local who can tell you what you have and whether it would create a problem to use it in a high humidity application.

If your particular material will work for this purpose adding a register to it should be a snap. Simply cut a correctly sized hole into it and screw a couple of screws into it. It should be able to support the register with just two screws. If it's too thin, cut a couple pieces of 3/4 inch thick and 2 inches wide wood at least as long as the register is high. Once the hole has been made, put a piece of wood INSIDE the hole and hold it to where the edge of the wood is at the edge of the hole. The wood will be inside the duct and only the edge of the wood should be visible. Put two screws through the duct material and into the wood. That should hold the wood in place. Do that on both sides of the duct opening. Next, place the register in the opening and screw it into place. This will "sandwich" the duct material between the register and the installed pieces of wood. That will hold the register fine.

Before you do anything, make sure you are working with the return side of your unit. Your description almost makes me think that the metal part of your system is the return side.

[billpa]

yeah thats what I was afraid of. Im going to research futher to see who makes the duct board. I was researching and saw a few companies that make it with a lining on the inside that prevents moisture from getting trapped inside of the fiberglass. I will look into it.

It makes me wonder. When we first bought our house, we had a piece of our furnace recalled and a guy came out to install an exhaust fan. I dont know how it kicks on (not on all the time) But it basically exhausts outside of the house. I dont know what exactly it is exhausting though. Perhaps I will snap a few photos.

Bummer...I thought I finally figured out how to get it more comfortable down there. I suppose I will just keep running the dehumidifier. Thank god I didnt add a return register down there yet.

Thanks!
billpa

[capncapo]

Have someone come out and give you an estimate on replacing it with tin. Or, if you're very handy at all, you may be able to do it yourself. You can buy pre-made sections of duct.

If it's nothing but a straight run from one side to the other, it should not take a pro long to do at all.

It may be possible that you are venting moisture because of the buildup in the ducts. The vent could be running off of a humidistat. It wouldn't surprise me.

[capncapo]

Some info for those witth 90% efficient furnaces:

Most furnaces use indoor air to supply the venter blowers ( if they have one ). Furnaces with a standing pilot don't have a venter.

Because these units use inside air in order to exhaust flue gasses, when the furnace runs it is exhausting humidity. Between the air outside being dry in winter and the exausting of flue gasses, it is conceivable that your humidity problem could totally disappear in winter with this mod done. Much depends on how "tight" your home is AND how well it is insulated.

Furnaces with a 90% rating DO NOT use indoor air to supply the venter and therefore will never reduce the humidity in your home. This mod will help you spread humidity throughout your home . The added humidity will allow you to reduce your thermostat setting which, in turn, will decrease tank evaporation rates but you will have to use some other method to exhaust humidity from your home in winter.

[hawk66]

Originally posted by capncapo
You want to open the sheet metal ( provided that it is, in fact, part of the cold air return ). Don't touch the cold air intake.



My n/g furnace is 35 yrs. old. No a/c so not a solution in summer but could help in winter. I have returns upstairs that run to the furnace, tee'd into this ductwork is a 6" pipe to an outside vent. Best as I can tell drawing additional air to the furnace. Is this what you are referring to as the cold air intake. This pipe runs through my proposed fishroom into the return duct. Why is it not a good idea to cut into this to draw from the fishroom? Thanks

[capncapo]

First, you'll have to tell me what you mean by "n/g".

[billpa]

I think he means natural gas

[capncapo]

I thought he meant No Good!

The reason that I told Skippyreef not to cut his is that it is being used to provide "make-up" air to his furnace. This will prevent a negative pressure situation from happening when exhaust air goes out his flue. The air going out has to be replenished from somewhere and without a source to get it from, it tends to draw air in down the flue as the hot air goes out the very same flue. Needless to say, the flue won't be working like it should and will often draw carbon monoxide back down into the house. His is not connected to his furnace and make-up air is flowing into his furnace room as exhaust goes out. I would think his furnace rooom might get pretty cool in winter.

In your case, that cold air would come into your fish room. A situation I think you would want to avoid.

Just an aside.....

I have never seen an intake setup like yours. Why would they want to draw in cold air from outside to heat when they could be re-heating already warm air? Could be that that is how the contractor decided to get some make-up air into your house.

Needless to say, I haven't seen everything.

[capncapo]

Hawk66,

One more thing.

IF your air intake is on some type of damper that opens when the furnace is on and closes when the furnace shuts off and IF there is a reasonably good draw on that line, it could be used to draw humidity from your fish room BUT unless your furnace can pull that type of draw, one or the other ( fresh air intake or fish room intake ) will be lacking. You could try to put a sort of "choke" in your cold air return to guarantee that the intake line is bringing in more air than the rest of the cord air return duct.

To do that, you can cut a slit in your return at some point that comes AFTER your Tee. You can bend a piece of tin in the shape of an "L" and slide the top part of the "L" into the slit. The bottom part would be used as a way of holding the piece in place. Just screw through the bottom of the "L" into the duct and then tape up whatever small slit that remains or just simply tape the thing in place. The size of the top of this piece will determine how much air can get past it. You can experiment with different sized pieces to see which gives you the amount of draw that you want.

[hawk66]

I agree it is an odd set-up. I'll be checking into it. Thanks for the help.

[skippyreef]

This is my make up air return. As Capncapo said I have an additional line for the cold air return. It does pull in more make up air when the furnace is running in the winter and makes it a little chilly by the furnace.http://img.photobucket.com/albums/v240/skippyreef/Picture031.jpg

[skippyreef]

here is a length shot of the HVAC line on one side of the basement.

http://img.photobucket.com/albums/v240/skippyreef/Picture033.jpg

And this is my old 180 LOL (found a pic of it in my album) I am hoping to do much better after this new tank is up!

http://img.photobucket.com/albums/v240/skippyreef/Dscn1807.jpg

[Whaledriver]

If you put in a air to air heat exhanger you can warm the air in the winter or use the heat for to save money in the winter

[outtacash]

Ahem.... a very basic question here. Is everyone cutting holes in their cold air return ducts because there are NOT existing vents in the room already?

More specifically, if my tank 270g total vol. is in a room that already has a cold air vent, I don't need to perform this mod? Should I try to hook into the cold are return closer to the tank?

Would it be better to have a good ceiling fan to make sure that the humid air is making it to the cold air vent? or should I spend the money on a local dehumidifier (an less attractive option given what I have read so far) ?

Thanks to those who respond.

[capncapo]

Does your tank room have a cold air supply vent or a cold air return vent?

If it's a return vent then you don't need to do the mod. If it's a supply vent then I would add a return vent to remove humidity from your room.

The hottest, most humid air should rise to the highest level in your room. That is where you should locate the return so you can incorporate the hottest and most humid air into your system.

A fan should not be necessary.

A deumidifier may/may not be necessary. I would wait and see how things are after you perform the mod ( if necessary ). A dehumidifier will add quite a bit of heat to your room which will cause your rate of evaporation to become higher.

[outtacash]

Cap, thanks for the response.

I should have been more specific in my question, my tank room DOES have a cold air Return (and supply).

Another quick question:

I'm in a backsplit so their is also a door right beside the cold air return that leads to the basement. The furnace is just a the bottom of the stairs.

Is it better to leave the door open, and let the humid air go downstairs by itself (which doesn't sound like it would work very well because you said the humid air rises) or should I leave the door closed?

Thanks again.

[capncapo]

Outtacash,

Kind of a double edged sword.

In winter, you would most likely be fine doing it either way but keeping the door open could possibly be of some benefit ( not a great amount, but some ).

If any air that is cooler than the air that is more or less at the top of your stairs happens to get into your house, it should go down the stairs until it hits a point of equillibrium of temperature. Whether it sinks all the way to the basement floor or not really doesn't matter. The cooler air will be less humid than the rest of the air in the basement and will therefore help to dry that air.

I would also put some kind of a closeable vent somewhere in the wall of your fish room that will allow air from the rest of your basement to enter the room . I would locate it as close to the floor as possible so that it would be drawing in the coolest air. In winter, I would close the register that feeds warm air from the furnace. When the furnace runs, the return will draw the warm moist air out of the room and, at the same time, fill the fish room with cooler air. That should help cut down on evaporation.

In summer, if you leave the dooor open, your coolest dryest air will sink into the basement. That is something that I would think that you would not want to happen. I would keep the door closed in summer.

I would also close the vent loocated in the wall of your fiish room and open the vent from the AC just to keep the fish room cooler and to reduce evaporation ( because of the cooler temperature ).

Hope I didn't confuse you.

[skippyreef]

Capncapo and all who have done the Mod:

How are things going first off

Second her are some pics of where I am and where I want to put the mod and the intakes to the utility room:

In the following pic teh cold air line is one the left. I need to do a take off I think in the furnace room and locate the vent at teh top of the wall. I really cannot do it in the ceiling now because of the way I had to frame it but at teh top of the wall will be nearly as high. I also want to place the vents in from the furnace room at teh bottom of this wall. I have an additional cold air inlet / make up air to prevent CO from coming down the flue that is code here in MI,
http://img.photobucket.com/albums/v240/skippyreef/Picture098.jpg

This is the tank. The ceiling will be greenboarded before the rest of the soffit is built around the tank to ensure a tight seal in there and to protect the mechanicals from the air adn humidity. I want to put the air to let the colder air in the room at teh bottom of the wall on the left which means I need to re-insulate after I get the vent.
http://img.photobucket.com/albums/v240/skippyreef/Picture099.jpg

This is a ceiling vent above and a few feet behind the tank to let in A/C in the summer and heat (as needed) in the winter
http://img.photobucket.com/albums/v240/skippyreef/Picture100.jpg

This is a vent I added to help condition the air in the viewing room.http://img.photobucket.com/albums/v240/skippyreef/Picture101.jpg

This is a pic again if te furnace adn the seconday fresh air make uphttp://img.photobucket.com/albums/v240/skippyreef/Picture102.jpg

And this is my 290 CFM fan that will be on a temp/de-humidistat controller in the room behind the tank.
http://img.photobucket.com/albums/v240/skippyreef/Picture080.jpg

[capncapo]

Looking good Skippy!

Looks like you're following the plan perfectly. Very nice work.

I'd be more than happy to give you some constructive criticism but at this point I have none.

Keep up the good work and let me know if I can be of any help.

[skippyreef]

Thanks Capncapo.

I think this will work out well in the end.

[BenDaddy]

For some reason, I can not see Skippy's pictures. Any chance you can post them to your gallery?

I too live in SE Michigan, and have my 180 currently being built into the basement. My fishroom is also my mechanical room (furnace/AC (x 2) and water heater). I think I have the 90% efficient furnaces, becase the house is 2 years old and I have the black flexible ducts coming into my cold air returns from the outside (which are currently housing a yellow jacket hive).

Both of the cold air returns travel right across the top of my tank. So I can simply add a register to each of these?

[skippyreef]

The pics are visible to me LOL that is weird.

Are you having issues in the basement?

[ostrow]

I just wrote to capncapo but then decided to post here. I have a new furnace, a Lennox variable speed one, efficience in the 90s somewhere. There is an a/c system as well. When they installed the furnace they did something to the chimney that included a chimney liner. Not sure what else. This system is supposed to have the blower on 24/7 but the wife often sets it to auto. That cuts down on efficiency of the ac/furnace.

Anyway, my basment fishroom has a 150 sump and a 75 fuge. Humid. There is a door and walls in the room, but it is hardly "sealed". Was going to get an exhaust fan and vent out the window but now worry about negative pressure.

The ductwork has lines for supply and return (intake). I have a vent in the supply, but the intake is closed.

Would a register to allow air intake into the furnace/ac system be helpful or bad? I have the supply register open all the time. Would I keep the intake open all the time, assuming one would help?

What about the door to the room? The furnace is in the center of the basement, about 15 feet from the room. There is a gap under the door so air can get in. But it seems seasonally there is a difference about when I want the room more sealed and when I want it more open.

I'm confused, as this post can show. Basically, with my setup do I:

1) want an opening for air intake in the room;
2) do I want that opening taking in air year-round;
3) what do I do about fresh air flow into the room re: supply vent/door to room;
4) what are the negative pressure worries here, if any;
5) what about the blower/fan, should it go to auto?

Thanks everyone in advance. I need to get the humid air out soon!

[skippyreef]

I would look into the mod and other things on this thread.

[ostrow]

Well, I am still trying to figure out all of this. There does not seem to me to be one single "Mod" discussed here.

Question: capncapo suggests most of the humidity in winter will go up the flue. Why is that? Wouldn't it ALL get recirculated throughout the house?

If the house is too humid in that event in winter, then what? Back to the exhaust fan out the side of the house?

[skippyreef]

I have a reduntant system in place. the cold air intake and the exhaust fan

[skippyreef]

I have a reduntant system in place. the cold air intake and the exhaust fan

[ostrow]

I see. No fresh air intake on my furnace BUT very old house, not at all in need of one I am told.

So I should do the intake into the system from the fishroom and also have an exhaust fan for use in winter if I don't want all that humid air, if I understand right?

Gotta get a register that can close for that intake, like having a supply register!

[skippyreef]

thats right. I do have afresh air intake and a back up to prevent negative pressure (code now in new houses here in my area). I also have teh air vent over the tank and one in the viewing room as well. Plus I am being conservative on hte lighting and using 2-250 watt MH in the LAIII reflectors. This helps reduce heat from lights.

[BenDaddy]

Skippy,

Still no pictures (maybe has something to do with the settings on my work computer). Anyway, no I am not having issues yet, but the system is not up yet. The carpenter is framing the tank in as I write this (at least he is suppose to be doing it today). I am just trying to anticipate issues, and engineer solutions while I still have some flexibility during construction.

This thread has be very helpful, and gets me started at least.

Capncapo, your consultation is very much appreciated!

[skippyreef]

I live near Ann Arbor if you ever want to come out and look at things :D that is not a problem. I will be home all weekend working on this.

If you PM your email addy I will send you a progressive set of photo's and answer any question you have about them.

The cold air return is a good idea in a basement anyway and this is sort of how the humidity is removed in the summer from your house because that air goes into the system (from the top where warm humid air is) and the humidity gets pulled out. I ahve learned a lot about basic HVAC theory while doing this project. Warm air cannot be destroyed per se just moved and it is moved into the A/C system where th ewater is pulled out and it is cooled down.

Also in the winter you will want some vents for heating near teh floor to keep air currents moving down there. Hope this helps you and PM me and I can send you pics.....

Mike

[mwood]

If I add a vent to the cold air return, will I get more moisture on the windows upstairs in the winter?

[ostrow]

From the HVAC folks I have spoken to it is a real possibility. It all depends on how much and how dry the air is that it will mix with, and how well the burner "dries it up" as it were.

I plan on getting a supply register to use as the return vent, so that I can regulate the intake if need be.

I also realized that days like today, when it is cool enough to turn off the a/c and open the windows, with the furnace system off, are the worse for basement humidity and that a return vent will do nothing to help that. Seems in any event a dehumidistat/bathroom fan vented to outside is needed.

[skippyreef]

it is realistic to have a fan on a de-humidistat to aid in mitigating the moisture as an augmentation to the cold air return.

[ostrow]

It's all getting expensive looking... what I wanted to avoid. May look into the dehumidifier option hoping for sales in this off-season...

[skippyreef]

I paid 127.00 shipped for a Cap-1 de-humidistat that works on temp and humidity levels.

The fan was 169.00 (290 cfm whisper quiet panasonic)

so that cost me 293.00 combined and adding the vents cost another 60.00

so its 353.00 approx all together and thts about what a decent de-humidifier cost.

I look at it like this though:

House would be >250K to replace LOL

then I will have nearly 12K in the tank.......

So this is a drop in the black hole of reefing money pit :D

[clamdigr]

Hmm. This has me rethinking my set-up. Currently two blowers, one on a dehumidistat for the tank room and one that comes on with the halides for the light hood (also in the room). Both vent to outside. I have noticed the basement is warmer in summer than before becuase of the fans sucking in warm (hot) outside are. The basement is finished but I can add the supply and return ducts to the tank room easily and use the current set-up for redundancy. What I wonder is, what about the heat from the lights? How do you handle it? Blow it outside? Blow it to another room where the heat isn't a factor . Or just let it stay in the tank room? Anybody got a diagram they could post?

Mike

[skippyreef]

Well if the room is not air tight the heat should move up and hopefully to another area.

What I have is a ceiling vent just behind the lights to drop cold air in the summer. The room is like 70 SqFt adn that vent will cool the area. But I also dropped in another vent in the viewing room to keep that area cool as well. this will also impact the tank temp. The fan will kick on when the humidity rised to abouve 45% (this is what I thnk is reasonable) or teh room temp hits 78

the air that is pulled in through the other room will be cold and dry. the vents into the room are going to be placed at teh bottom of the wall to pull in the coldest air near the floor.

the cold air returns are up high to exhaust the warmer humid air that will be neat the ceiling in the viewing room. there is no way for me to make the fish room behind the tank 100% airtight because of the way the tank is to be viewed so this will all work in tandem to keep things comfortable.

[Whaledriver]

Why not have a air tight hood over the tank. You could have outside air in one side and hot air out the other side. Just get a fan on a thermostat

[ostrow]

My display is above my basement in living room. Don't notice any heat from the lights. Must dissipate fast on its own.

I'm now leaning towards air intake vent + dehumidifier and skip the exhaust fan. Too many complications that I can see. Negative pressure/CO risk, bringing in the unwanted outside air that is too cold in winter, too hot in summer, etc. I can't get a handle on how to do it safely.

I figure with the air intake on the furnace/ac system, that the dehumidifier only will be needed on days when that system is off, primarily spring and fall days.

[capncapo]

The exhaust fan would be much more cost efficient than a dehumidifier provided that an outdoor source of air is included.

[Whaledriver]

If you dont want outside ventilation why not run a chiller and a closed top tank. Get low iron glass tops made and dont worry about the humidity. Just use a good skimmer to help with O2. Instead of kalk use Calcium chloride. You might have problems with low PH but you can just keep you ALK at 10-11 and you should be ok. A refuge on a reverse light cycle would also help with the PH.

[Gudwyn]

In a tank room with easy access to exterior walls, I'd recommend self installing an HRV. When the HRV is stand-alone, the install is simple (mine was pro installed in the duct work and is a complex job).

HRV's equalize humidity with the outside and don't lose a lot of heat. In a stand alone install, they also can't create any problems with your HVAC system.

[clamdigr]

capncapo- I currently vent my basement fish room outside, the light hood is vented to outside as well. I bought the supplies to add a cold air return and supply vent to the fish room and plan to use the outside vent as a back-up and not vent the light hood outside anymore. I'm concerned about the heat from my light hood building up in the room between heat/cold cycles as the room is small. So...do you see a problem if I put, say, an ice cap 4" fan on the hood and run flex hose to the cold air duct so the heat dissipates in the duct between cycles. This would mean two cold air returns in the room, the normal one and one that is force fed.
Or is this crazy talk.

Mike

[capncapo]

Mike,

No, it's not crazy talk.

It will help prevent a build-up of heat in your fish room.

Something to consider though is that the heat will not remain in the cold air return ductwork. It, like all heat, will rise which means that it will eventually make it to your upstairs living spaces. In winter it would be no problem but you may not want that to happen in summer as the heat will cause the A/C to run more. Along with that, the added humidity may necessitate the lowering of the thermostat setting to retain the same "comfort level'.

If your cold air return happens to be located in the floor beneath where your thermostat is mounted on the wall ( which should NEVER happen but often does ), it could also give a false temperature reading and make your A/C run more than needed as well as make your furnace run less than needed.

The bottom line is that it will not "harm" anything if you do it. Whether it would be something you want to do can only be determined by trying it and seeing if you like the results.

[clamdigr]

capncapo,

Thanks for your help, I'll try it and see how it works.

Mike

[ostrow]

Gudwyn: yeah, but where limited resources are in play, which for some they are, that is a fairly expensive option as far as I understand it. I'm looking to spend a hundred or two, not a thousand or two.

Whaledriver: the humidity is from my 5x2x2 sump. Covering it is not really an option as I have an ASM G5 skimmer, and the drain pipes into the sump. Not realistic as far as I can see. I have no need for the expense of buying or running a chiller with 50% of my water volume underground, so that's good. But the humidity is a threat to the studs and floorboards above!

This is a truly informative thread and thans capncapo for all the advice! Gonna take it step by step and do what I have to when I need to! Will probably be doing the vents to outside in spring...

[skippyreef]

with the cold air returns in the basement this should help in the summer / winter. In the fall / early spring I think the exhaust is a good option. I finally mounted my fan and it is just behind the tank. I have the supplies to cut in the duct work and the wall vents. I have waited to cut in until the drywall is hung (the furnace room is right behind the wall and so is the cold air trunk line) so that I get teh best position. My ceiling is sealed with greenboard as well to prevent damage.

I think this thread is a great resource and offers some great ideas.

Here is a link to my thread with photo's of my project to date. MAybe that will help with some ideas because the entire basement has been planned to deal with potential humidity issues and strategies to mitigate the humidity if it becomes an issue.
http://www.reefcentral.com/forums/showthread.php?s=&threadid=654443

[kwl1763]

lots and lots of good info in this thread. I am in the plaaning stages for a 400G in my basement and looked at my unit down there yesterday. The good news is that I locted my cold air return. The bad news is all the ducting is that flexduct soft stuff. There is plenty of room where they all meet to add something thoug.

So here is the question do I just cut a hole as high as I can on the intake part at the unit and add the register or would it make sense to cut a hole and run a duct up to the close to the ceiling and put a duct there? I'll try to get some pics up tommorow.

[capncapo]

If it were me I would run the duct. That way you wll be taking the air from the most humid area and you will be getting it before it has a chance to become "diluted" by less humid air.

I would also make sure that your existing ductwork is flexduct and NOT ductboard. If it's ductboard, I don't think that I would do the mod without asking a local professional if there will be any negative consequences.

[kwl1763]

Ok here goes. Purpose of the post is two fold. Documentation of what I'm doing with pics but more importantly to run what I'm going to do by people who actually know what they are doing :D

First here are the pics of the unit itself. First is from the front. I'm actually standing in the room where all the equipmen tand sumps will be.

http://kwl1763.com/Reef/Nov_05/New_Tank/ACfront.jpg

Here is the right side still in the fish room

http://kwl1763.com/Reef/Nov_05/New_Tank/ACright.jpg

Now here is the back side which is where I'm planning to tap. It is actually under the stairs. In this pic the fish room is in front if you look "through" the AC but the actual tank is behind on the other side of the stairs.

http://kwl1763.com/Reef/Nov_05/New_Tank/ACback.jpg

The right side there is the return side. Hopefully someone can look and verify but I'm 99.9% sure. The plan is to tap the back and then run 6" flexduct up and split it with one register over the tank and the other over the fish room. Does this sound reasonable. Any pitfalls I should watch out for?

My other question regards pressure. If I'm sucking from the basement and distributing to the first floor are ther any pressure issues to be concerned about?

[capncapo]

While looking at a unit , the return drop is typically the one that extends closest to the floor BUT if you happen to have a downflow furnace, that would not be the case.

The easiest way for you to determine which side is which would be to follow one of the flexduct run from each side to see where it goes. One of the sides will go to your registers. Registers blow air out. The register side is the supply side and NOT the return side.

The return side also typically has considerably fewer ducts going into it. The return sucks air in.

There wll be no pressure issues and the plan sounds reasonable.

[Chris Witort]

capncapo, I had a question about HVAC systems. Could a system that has air conditioning and heating have a humidistat installed that would turn on the AC when humidity gets above a certian level but also run the heat side to keep the temperature in the space where we want it? Sort of like the defrosters work in a car?

[capncapo]

Yes, it could be done.

Never havng done something like this, I would guess that it could possibly be very difficult to control exact temperatures and would most likely affect the life of your A-coil.

It would be even more dffiicult to pay the energy bill.

Why not use a dehumidifier or HRV intead?

[Chris Witort]

Wouldn’t it be accomplishing the same thing without having to buy the dehumidifier? I'm guessing that it would also consume the same amount of energy either way, assuming equal efficiencies. Does a dehumidifyer use the same method of extracting water from the air as the AC coil by condensation.

[Mantis]

When the heat is on most of the humidity your worried about will get removed by the furnace when it runs.

I love the extra humidity our tank gives us in the winter. Before the big tank our house used to get down to 30% humidity. I'd be really unconfortable.

[capncapo]

Chris,

Yes, you would be accomplishing the same thing without having to buy a dehumidifier.

No, you would be using considerably more energy ( about twice as much ) by running both units at the same time.

Yes they work pretty much the same but a dehumidifier typically uses a cold surface instead of a coil.

Bottom line is that it would be a huge waste of money to have a furnace and an A/C "dueling" with each other.

The whole purpose of the suggested modification is to alleviate the humidity for little to no additional cost.

Like Mantis pointed out, the humiidity is actually desired by many folks during winter. Where I live, many people have humdiifiiers installed for use during the winter months. They eliminate many undesireables such as static shocks from walkng across carpeting and nosebleeds from dry air. The humidity also allows for a reduced thermostat setting while retaining the same "comfort level". With the projected hike in energy prices this winter ( up to 75% ) I would think that the very easy and inexpensive mod would appeal to anyone who lives in an area that gets cold.

[mwood]

The added humidity is a good argument in theory, but I'm a little concerned about it in practice. I woke up to a lot of moisture on my windows this past weekend. I own a new home here in Iowa. When temps dipped down around freezing, the condensation build up pretty quick on the windows. I currently have 80% humidity in the basement and 50-60% on the main floor. Distributing that 80% around the house scares me a little as I don't want to see more water on the windows.

Marcus

[capncapo]

Marcus,

Too much humidity is just that, too much humidity and it will quite possibly take a combination of methods to keep yours in check.

Your new home is most likely fairly tight and efficient so it's not likely that you will have any leaks where dry air can make it's way into the house or that humid air can make its way out.

Do you have an electric or 90% efficient furnace? Neither of these allow humidity to escape up the flue.

If your home is super insulated, even an 80% efficient gas furnace may not run enough to be effective at removing an excessive amount of humidity.

Your best choice may be to go with an HRV to allow some of the humidity to escape as well as some of it beng distributed throughout your living spaces.

[mwood]

I have a train gas furnace. I'm not sure of the efficiency factor, but it doesn't have a pvc air intake, so I don't think it's a high effeceincy furnace. I just bought a 65 pint dehumidifier and may add a vent to the cold air to see what happens. If I don't like it I can always close it. What is a HRV?

[capncapo]

Heat retaining vent.

Basically an air exchanger that retains about 80% of the heat of the air that it is venting outdoors. It vents your humid air out and brings dry air in while retaining the heat.

[mwood]

That sound's like a neat trick. I wonder how effective that would be a negative temps?

PS, got a link?

[capncapo]

http://energyoutlet.com/res/hrv/

http://www.toolbase.org/techinv/techManufacturers.aspx?technologyID=122

http://yourhome.honeywell.com/Consumer/Cultures/en-US/Products/Ventilation/Energy+Efficient/Default.htm

Tons more info on the web. Do a search on HRV or air exchanger.

[law086]

capncapo - Maybe this is too simplistic of a question, but, if money wasn't an issue, and you had a window or two to play with, what would be the easiest way to take care of humidity in a fish room? Is there a simple, ultimate device that can be used?

[capncapo]

With money not being an issue I would think that an A/C unit dedicated to the fish room only in conjunction with a good sized dehumidifier could solve the humidity problem to a satisfactory degree.

The A/C unit would run long enough to satisfy the thermostat (and would be dehumidifying while running ) and would cycle off and on as needed. The dehumidifer would run 24/7.

[law086]

Thanks - can you comment on how well an AC unit alone would lend to the job? I'm guessing my future fish room will be in the area of 60-70 sq ft and I have no problems running an AC unit in just that room.

I live in the northeast, so heat and humidity is typically only a big problem a few months out of the year.

Ron

[capncapo]

An A/C should do you fairly well provided that the thermostat in the room is set reasonably low. You want the unit to run at least part of the time when your lights are off otherwise you'll only be dehumidifying 8 hours or so a day.

One other suggestion would be to look at a "mini-split" A/C instead of a window unit. As far as I'm concerned, window units just don't seem to dehumidify as well as "normal" units do. A mini-split system is for all intents and purposes identical to a normal central air unit except smaller.

[law086]

Thanks for the suggestion. The only downside to those mini-split systems is the price!

I guess it would almost even out if it would replace a dehumidifier too.

Thanks again,
Ron

[law086]

Just thinking out loud here, but looking at a unit like this:

http://www.air-conditioners-america.com/product.asp?product=MPF-10ER

It's removes about 15 gallons of moisture per day. That sounds like a whole lot to me, with 10,000 BTU's of cooling power to boot.

Doesn't something like that sound like a home run? What am I missing? I doubt many tanks evorporate more than 15g per day. $429, and no window needed.

Ron

[capncapo]

Theoretically, it sounds great BUT I have never seen an air condtioner that needs nowhere to put the heat.

Air conditioners are not designed to "make" cold air. They are designed to move heat from one place to another. That particular unit moves the heat to where? It never leaves the room so how does it make a room cool?

In my experience, you get what you pay for and you're not paying much for a unit that promises an awful lot. Personally, I would look elsewhere.

[skippyreef]

if I were to do an independant A/C I would opt for teh split A/C unit myself.

[BigEasy]

caoncapo,
I just found this thread and have read through the whole thing. Excellent thread for an issue I'm not sure enough people take into consideration.

I'm planning a fish room for a 500gal or so system in a house that isn't even built yet. Will have the fish room on the main level of the house and viewing area will be the family room. I thought I needed to address heat, cooling and moisture. From the links you posted on on the ERV/HRV systems, seems this is a good way to go. Looks like the ERV/HRV could take care of the humidity issue pretty well. Is that accurate?

I had planned on venting heat from the lighting box to the outside using a fan on one end to push air into the box, another fan to pull it out and up through some flexiduct to an outside vent. Would that still be needed with a ERV/HRV?

As for the chiller, I had planned on letting it vent into the room. Hadn't figured out a plausible way to vent to outside on this one.

Any advice would be appreciated.
Steve

[skippyreef]

Capn'

I got the fan installed this last weekend and have it on a cap-1 controller. I also have been monitoring the intrinsic humidity of the basment and temp. I run a RH of 45-50% at 65 degrees down there right now. I am adding a 60" wide 42" tall window in the spring to add more light also.

I think with temp being low I might not evaporate as much water as I do out of my liitle tank on the first floor which averages 9 degree's higher. I also have a little window in the utility room that can be opened a little for make up air this winter directly into the room.

Suddenly I am thinking that cooling and evaporation may be ok and it will be more of a challenge to keep the tank warm enough :D

[law086]

capncapo - I would ASSume an AC unit like that would have a vent that you'd have to hook into a window. I guess my statement about not needing a window wouldn't exactly be true. If it doesn't.. then, yeah, good point, what happens to the warm air.

Thanks for all your comments.

Ron

[capncapo]

Steve,

While HRV/ERVs sound like the perfect solution, they have their limitations.

For example:

ERVs are supposed to remove humidity from incoming air and send it out with the exhaust air and they do .... but only to a certain degree. If you live in an area where the relative humidity remains low most of the time they will do you good but, in that case, so would anything that exchanges outdoor air for indooor air.

If you live in an area with high relatiive humidity, the dessicant wheel that does the transfer of humidity becomes saturated so quickly that it becomes ineffective almost immediately.

Also, ERVs are supposed to retain a percentage of the cool air that you would otherwise be ventiing outdoors. Great concept EXCEPT for the fact that folks with reef tanks hardly ever vent cool air. Even when the lights are off we are still heatiing the rooms because we keep our tanks at normal reef temperatures which are higher temperatures than most people keep their homes in warm weather.

When it comes to reef tank setups, I'm not a big fan of ERVs for those two reasons but, then again, I live in an area with a high relative humidity and keep my thermostat temperature set below the temperature that I keep my tanks.

HRVs are great but have a limited season as they are for use in cool/cold weather.

[capncapo]

law086,

I looked at your link again and actually read everything this time. There is a window/wall vent kit for it. Didn't really look too deeply at the info because of your comment about the vent last night. Couple that with the name "portable" and just couldn't see it being much.

[law086]

capncapo - based on what you see now - how would you rate it?

[capncapo]

Skippy,

Sounds like the cooler months will hopefully be a breeze for you and yes, the cooler temps will reduce your evaporation rate considerably.

Being that I am the jealous type and despise anyone who has a tank larger than I do :D ..... a word of caution for you.

When most folks set up a new tank in the basement, they usually say 'Humidity issues ...... what humidity issues?".

What they don't realize is that EVERYTHING in the basement that is capable of absorbing moisture is doing just that and that any potential problems could be weeks, months or even years in the making. Once everything has absorbed as much humidity as it can, from that point forward it has nowhere else to go and builds up in the air. That's when the real problems begin.

You've pretty much covered all bases with your setup and I don't foresee problems for you but keep on your toes. Stranger things have happened but I would suspect that you will be more proactive than reactive anyway. The setup is looking great!

[skippyreef]

Thanks Capn'

My Father in LAw and I used greenboard to stop the absorption as much as we could in terms of teh wood wicking the moisture. The cold air return will help and I added heat registers as well. When I heat is on the basment temp is pretty comfortable at 68 degrees. The vent fan really does a wonderful job and we may very well use it when we are sanding in the basement in a few weeks. I am so glad now that I bought something that is large and quiet. If it comes to it I will install a split A/C in the fishroom itself. I have a friend who is a licensed HVAC technician that can do it. First though I am putting in the window. I figure with a large window there will be little air leaks here and there and It will also afford me the ability to open the window in hte transitional seasons of spring and fall.

I also decided to use cheap air filters and change them regularly to keep the furnace breathing easier in the winter and this will hopefully keep things comfortable.

I have greatly appreciated where this thread had gone. I have actually learned alot about HVAC and how my house works from this thread. I understand the heat exchanger now and what my A/C coil is doing for me and why I have those return ducts in my house! I never knew what any of that was for before, just that I hated painting around the ducts in the wall :D

It has been important for me to plan for this well and to consider all the things that are not considered if one rushes into a project with eyes wide open but the peripheal vision blinded.

So thanks again

Mike

[capncapo]

Ron,

In general, the specs look good. My only concerns would be reliability and serviceability.

I have to admit that I'm not familiar with the manufacturer so any comment about reliability would be foolish on my part.

One thing I can say something about is serviceability.

Most self-contained A/C units these days are more or less throw away units. When they break, you throw them away and buy another. After all, most people don't want to spend $100.00, $200.00 or $300.00 to fix a unit for which they only paid $400.00 brand new.

That being the case, it's getting harder and harder to find someone who is willing to work on those types of units. Many technicians ( including myself ) have wasted a bunch of time going to customers homes, diagnosing problems and then giving estimates on the repair cost only to have the customer say that it isn't worth the cost to repair and that they will just buy a new one.

Needless to say, it doesn't take too many of those money losing service calls before you decide that they aren't worth dealing with.

I guess the bottom line would be that if you know or can find someone who would be willing to service the unit, it could be worth a try if something else is not wiithin your budget and you are willing to take the risk ( maybe very low or very high ) on reliability.

I'm not trying to sound negative at all but am just tryng to give you all of the facts that come to mind.

Hope this helps!

[law086]

Fair enough. Thanks for your input!

Ron

[bstone]

capncapo

I wanted to see if you could give me some recommendations for humidity control with my new tank setup/fish room.

I have a 3 car garage that is two wide and on the left side it is two deep. I closed off the deep side and made it into my fish room. My tank will be inwall which is my family room. I have a window AC unit in my fish room that blows into the garage. This is where my HVAC unit for my house is. I was also planing on running a dehumidifier in my fish room. I am also going to put plastic up on the walls and ceiling before the drywall is put up. Will this be good enough? Or, should I add a vent to the outside and then a fan to suck air out of the fish room and into the garage that would be controlled by a humidity meter. This way I can pull air from the outside into my fish room and then pull air back out into my garage. Thanks for your comments!

[skippyreef]

This is the utility room ceiling behind my tank. WE decided we would drywall teh ceiling first and tape before we built teh final soffit around the tank and the last two walls to frame in the door leading into the utility room. This way the ceiling would be sealed up much better.

you can see teh register vent in the ceiling and the fan. I am going to use moisture proof shower covers over the lights.


http://img.photobucket.com/albums/v240/skippyreef/Maderiabeach2005150.jpg

http://img.photobucket.com/albums/v240/skippyreef/Maderiabeach2005149.jpg

[Chris Witort]

I hate to say this but, did you know that greenboard is not designed to span 24" on the horizontal?

[skippyreef]

we built everything 16" on center

[Chris Witort]

1/2" is rated for 12" spans, 5/8" is rated for 16" spans. If you have anything wider you would need to use standard 5/8" drywall or celing board. It will tend to sag slowly otherwise.

[skippyreef]

Thanks for the informtion. We read a lot before we purchased anything and everything is 16" on center as far as apans

[capncapo]

bstone,

A little more info please .......

Your fish room is the deep area of the garage.

How about an approxmate size. Hopefully it is insluated .... both the walls and ceiling?

Your furnace and A-coil are in the other area of your garage.

Is that area insulated also?

What will your total water volume be? Include tank and any sumps, refugiums, etc.

What is your ductwork made of and is it insulated?

Why do you think you want to bring outside air into the fish room and then vent your fish room air into your garage?

Any other info that you may think important?

Got any pictures?

Thanks

[Gudwyn]

"HRVs are great but have a limited season as they are for use in cool/cold weather."

HRV's will reduce humidity in an area with a large reef tank in most weather.

The one case where they don't work is when you are using AC in an area with high outside humidity (gulf coast for instance). In that case, the AC reduces the indoor humidity and an HRV just sucks humidity back into the house. But if you aren't running the AC, running an HRV in your fish room almost always helps.

As far as the question about sub-zero, yeah they work fine. Canada requires HRVs in all new construction.

[bstone]

bstone,

A little more info please .......

Your fish room is the deep area of the garage.

Yes, the garage on the left side is 2 deep. I converted that area to a fish room. It is completely closed off from the garage now.

How about an approxmate size. Hopefully it is insluated .... both the walls and ceiling?

18'-6"x11' ceilings are 9'. Yes, everything is insulated, ceiling and walls.

Your furnace and A-coil are in the other area of your garage.

Yes

Is that area insulated also?

Garage is insolated except for one side, and garage doors.

What will your total water volume be? Include tank and any sumps, refugiums, etc.

1000 gallons

What is your ductwork made of and is it insulated?

Not metal, its the plastic insolated type.

Why do you think you want to bring outside air into the fish room and then vent your fish room air into your garage?

No idea, that is why I need you assistance!:rollface:

Any other info that you may think important?

I have a window AC unit in my fish room the vents out into the garage. I do have a dehumidifier, if needed.

I will have pictures soon!!

Thanks for your help! Also, sorry for hijacking this thread!!

[capncapo]

bstone,

One more thing ........ what about heat for the fish room? Do you have that taken care of already?

[bstone]

Do you mean during the winter time? I am thinking the 2910 watts of lighting will keep the room warm. I have about 900 watts during the night time over my refugium and coral prop tank.

[capncapo]

And how about the floor in the fish room? Just concrete or have you done something else with it?

[Nataku]

First, I want to say this is a great thread.

I came to the same conclusion as skippyreef at least in theory . Summer time i would run a fan into the cold air return kind of like a 1st stage forced induction. Then in the fall and spring when the ventilation is not running to vent outside.

Perhaps there's a way to run both fans on the house thermostat. When the vent is running the fan on cold return will run. When the vent is off have the outside fan to run. that way humidity is constantly removed. In both cases i would run a low volume fan not to draw in too much outside air.

As well, I was thinking about protection for the exposed wood in the basement. Perhaps apply some type of wood sealer such as Thomson's water seal or polyurethane. I could use one of those airpumped sprayer for weedkiller / insecticide instead of painting it on.

[bstone]

And how about the floor in the fish room? Just concrete or have you done something else with it?

It is just concrete.

[skippyreef]

my fan will exhaust the room in something like 2 minutes. According to the calculations I did I could have gone with a 75 CFM fan to get 8 air exchanges an hour but I did not want the fan running all the time. I think it is best to get the humidity out in a timely manner :D

I also used the green board to cover up the ceiling and seal in the wood so that there will be minimal opportunity for the wood to act as a sponge for the moisture.

I think that by keeping the basement temp around 68 degrees that the tank will not evaporate at the same rate as it would if the temp was say 75. The cold air returns will also aidde in preventing any problems I think.

[capncapo]

bstone,

A few points for you.....

Were I going to do what you are about to do, I would first do something with the concrete floor. You could quite possibly find that it will influence the temperature in your fish room as much ( if not more ) as any other factor.

I'm also assuming that the door into the fish room is located in the garage? If that is the case, that will be another source of undesirable air infiltration that wiill also influence the temperature of the room.

What I'm trying to get at is that it's tough enough to control room temperatures in a fish room when there are very few, if any, external sources of heat or cold but to try to control them with a slab of concrete that only partially contained in a treated space and an entry door that opens to the same could prove to be a frustrating experience that would best be avoided. Personally, I would put in a raised, insulated floor and use an exterrior rated door.

You aren't that far away from where I live so I'm sure that you have those 0 degree days in winter. Your main lights should be plenty duuring the day but I'm not so sure about your other light being all that's needed on those cold nights

I would also consider adding some type of auxillary heat source just in case your lights don't give enough heat during a long cold snap. Your main lights should be plenty during the day but I'm not so sure about your other lights being all that's needed on those cold nights and it doesn't hurt to have a backup system just in case.

Now, on to the particulars ..........

You are going to have a buttload ( a scientific heatng and coolng term that means A BUNCH :D) of water contaned in a relatively small area. On top of that, you will be using lights that will create loads of heat so you are going to need to become very aggressive in your methods of controlling both the humdty AND the heat.

You will need to use both your window A/C and dehumidifiier. The vapor barrier you asked about should not be needed.

In addition to that, I would use some type of vent fan that is vented to the outside ( not the garage ) for use when the temperatures and humidity levels outdoors are acceptable enough as to allow for its use. You can't use them all of the time but when you can, using them instead of the A/C and/or dehumidifier can save you some good money; enough to pay for the vent many times over. Remember that if you add any kind of fan that vents air out of the house that you must have a way for outside air to come into the house.

I don't know whether you use gas or electric heating but most homes that use gas heat could stand some additional humidity in winter. I will assume that you have gas heat and with that in mind, there are a couple of ways for you to incorporate your fish room into your home heating and A/C system.

My preferred method would be to run some ducts ( supply AND return ) from your furnace unit located in the garage to the fish room. I would locate the return duct near the ceiling and the supply duct near the floor. If you connect the ducts to closeable registers, you can regulate just how much air goes through your heatng/cooling system and can also close them which would effectvely remove them from the system.

The second method would be to add some vents that penetrate the into the fish room from the wall that is common with your famly room. I would use at least a total of 4 closeable vents and would place 2 of them high up on the wall and the other 2 would be placed near the floor. Doing this will allow air to circulate from the fish room into the house both helping with temperatures and humidity and the best thing of all is that it would be strictly a passive system in that no fan would be requred to produce that circulation. With closeable vents the system could effectively be turned off and on simply by closng or opening the vents.

You might consider doing both of the methods mentioned above. I would do both as I would much rather have and not need than need and not have and now, while construction is going on, is the time to make changes.

Doing this will allow your home heating and cooling systems to help with the task of keeping the fish room environment within an acceptable range.

When it comes to very large tanks/water volumes and lots of MH lighting, much of the temperature and humidity control is a fly by the seat of your pants type of thing as every setup is unique and, as such, unpredictable. I would install as many contingencies as possible while constructing the fish room rather than go through the pain of tryng to add them after the tank is up and running. With serveral methods of control you will have the ability to "tune" the systems for optimal performance in every season.

Good luck!

[bstone]

capncapo

Thanks for the detailed description on how to control thew temp./humidity in my room. When looking at my fish room in relation to my furnace, it would be very easy to add a supply and return to the fish room. Also, adding closeable vents to the wall between the fish room and family room is also very easy. None of my drywall or insulation is up right now, so it would be very easy. Adding a fan that vents are from the fish room to the outside might be a little harder, but doable! The exterior of my house is brick, so I would have to cut through that.

What do you recommend as a sequence of events to do, lets say in the winter time to the summer time. Such as in the summer time open the vents from the fish room to the family room, then open vents for supply and return to AC if humidity and temp are still high, then turn on fan to vent out air to outside, then us window AC and dehumidifier?? Something like that, and then a different sequence for winter?

Thanks again, these are all great suggestions that I will implement soon!!

[capncapo]

bstone,

That is a question that would probably best be answered by you after studying the effects of each of the various methods on both your fish room and your house. Each of the methods will have a different "degree" of dehumidification and heat control that can only be determined after all of the systems are in place and put to use.

A couple of the methods ( vents in the walls and connecting ducts to your heating and coolng system ) will have an effect on not only the fish room but your home as well. Whether it will become noticeable to you or not depends on how much heat and humidity will be generated and brought into your home and how well your heating and cooling systems are functioning.

The use of a vent to the outside should only be used when outside humidity and temperature levels are within an acceptable range. Depending on how much heat your lights produce and the humdity level of the fish room, acceptable levels could be only on cool dry spring and fall days and nights or could possibly even include winter days. You'll have to experiment and figure out for yourself when to use the vent fan. I would try to use it as much as possible as it will be the least costly to operate of all the active components. Needless to say, you won't be using it much, if at all, during the summer months for sure

I wish I could give you a hard and fast answer on when to use what but to even attempt that could end up making a fool of me and making you mad or even worse. The best I can do is to tell you to study everything you can about how the various systems impact the heat, humidity and even other systems and then put into practice what you learn. Don't be afraid to experiment with different combinations of systems in different weather conditions and make sure that you document your findings for future reference.

Personally, I would try to use the systems that cost the least to run as much as possible and use the others only when needed.

Don't forget that dehumidifiers produce a fair amount of heat and that using the air conditioner in your home to cool the fish room will probably cost less than usng the window A/C unit ( depending on the efficiency rating of your home A/C ).

Good luck and post some pictures so that we can see your setup and your progress.

[bstone]

capncapo

Thanks for all your help! I needed this type of help when it came to humidity/temp control. I will end up doing everything except the sub floor. My stand is already built, so there is no way to get a sub floor up now! Thanks again for your help! Here is a link to my project w/ pictures.

http://www.reefcentral.com/forums/showthread.php?s=&threadid=694341&perpage=25&pagenumber=1

[bstone]

capncapo

I bought a exhaust fan for the room. I think its the same one listed on this thread. I am looking at controllers, do I want one that turns the fan on when just humidity is above the setpoint, or when temp and/or humidity is above the setpoint?

I can get a dual controller that turns the fan on when above the setpoint on the humidity, and then turns on the window AC unit when temp. is above setpoint. Remember, the window AC unit will be my last resort if my house HVAC unit can not cool the room enough. I kind of like the idea of setting up a controller that would have a dual output independent for both humidity and temp.. What are your thoughts, what would you use in this setup?

Thanks.

[capncapo]

bstone,

It would be nice to control the fan in an and/or fashion but I'm not familiar with a single device that will do that. You could wire a humidistat and thermostat in parallel to accomplish that. You might also need to add a diode or some other component to each to keep electric from "backing up" into a unit while it is off but the other is on.

That being said, a lot depends on the temperature and humidity level of the outdoor source air. It's a given that the exhaust air will be hot and/or humid but what about the air coming in? If it's hot or humid, you don't even want to use the fan.

I think I would also put a on/off switch on the exhaust fan AFTER the controls so that you can shut it off should outdoor conditions be less than desireable for its use. That would allow any controls attached to function normally but the fan would not be activated.

Personally, I would not use a combination device. I would use standalone devices. To use a combination device creates a situation where a single point of failure is possible. I would try to avoid that at any cost.

Something for you to remember when you are looking at purchasing these controls is that you will be looking at "line volt" devices. Most "normal" thermostats and humidistats use 24v that energizes a contactor ( relay ) that then switches a higher voltage on and off. Line volt devices are powered by 110v/120v and switch the voltages on and off themselves without having to go through a contactor.

Make sure that you get a heavy duty unit for the A/C. The fan won't draw heavy amperage so a normal unit should do fine for it.

[skippyreef]

In the summer months your better of with the A/C unit becaue of the hot/humid air outside. My plan is to install a split A/C unit in the spring seperate from my houses main A/C.

[bstone]

capncapo

This is what I was thinking about, take a look at the CT-DH-2 model. Or I can get two controllers, each separate - one for humidity to control the exhaust fan, and one for just temp to control the AC. Just curious if you had seen these controllers!

http://homeharvest.com/climatecontrollerscoolingdehumidify.htm

[capncapo]

bstone,

I have not seen those controllers before. The specs look like they would do the job for you provided that your A/C doesn't draw more than 15 amps. According to the info even that can be changed so I don't see why it shouldn't do what you want.

Something you haven't mentioned is your dehumidifier. If I were you, I would have the fan come on first, the dehumidifier next, and then the A/C which means you would need three controllers.

Again, it's just my preference but I would go with discrete devices just to eliminate the single point of failure. What can I say ........ there are some things that I can be anal about.:D

[Dag]

Capncapco,

My problem is not the winter, it's the summer. My A/C can't seem to keep the house cool. I've had three different HVAC companies examine my system, and all pronounced it fine, including the temperature of the air coming out of the registers.

It's a two-story house (about 3800 square feet above ground) and a basement. I have my 200 gallon display on the first floor, and sump, refugium, etc (about 120 g) in the basement. The tank is kept at 80 degrees, and there are three 250W metal halides above the tank.

There is a 4 ton unit on the first floor and a 1.5 ton system cools the second floor. Second floor is fine. First floor never gets cool enough. (Some might say that the 4 ton on the 1st floor is oversized, but when I changed the unit about 4 years ago, a 3 ton was initially put in, and when it didn't cool, I thought the problem was the size so I upgraded to 4 ton.)

I use a humidifier in the basement during the summer, and I keep the basement doors closed. Also, I changed all my recessed cans in the first floor ceiling to compact fluorescents.

Any advice would be appreciated.

[capncapo]

Aryeh,

There are too many factors coming into play to mention in order to give you the "right" answer. The biggest one being that I haven't seen your house.

A couple of things come to mind. Some are questions and others are comments.

How long does your unit run on a hot day?
When you had the condenser unit ( outdoor unit ) upgraded, was anything else done?
Do you have ceiling fans?

Something to consider is that the humid air will "feel" warmer and you will need to set your thermostat lower to compensate.

Even though you keep your basement door closed when running the dehumidifier, they create a tON of heat and that heat has nowhere to go but up. It WILL make it upstairs.

Reply to my questions and we'll go from there.

[nonot8946]

Has anyone tried simple passive thermal regulation?

Basically seal the tank off from rest of the house (not even the room but just the tank itself). (Most people's hoods almost do this already.) Have one vent that could allow you to pull in cool air leading down. Have another vent leading upwards (hot air rises) to a nearby exit to the outside?

You could put a fan in there for when you need more cooling/dehumidfying.

Provided the vent isn't too far away, seems like you could get decent air movement.

Since the more or less enclosed environment is small, it could heat up quicker, but it could also cool off quicker. Heat rising can draw in cooler air from near the basement floor.

However, since humid air is more dense, would it sink? Then this might not work, so you'd vent the high and low vents outside and have a middle vent with the fan to draw in the cool dry air.

Would the humidity be a problem? Well, I wonder because the hood and lights are basically right off the waters surface so they're pretty much exposed to really high humidity anyways, and everything else is ductwork. When you do expel the humid air, the volume is much less than say, the entire room, so the amount of cold air drawn in from outside is much less, so you have much less of an additional load on the furnace. If you want to warm the air passively, have a seperate vent to the outside that uses a solar heater (basically something black that the sun hits). The sun (during the day at least) can prewarm the air about 40 degrees.

Cost: some ductwork, and a bathroom fan. Even the cost to run the fan has to be cheaper than the thousands of dollars you are all planning to spend on the HVAC and heat exchangers.

The problems are for you guys who live where its hot and humid outside. Then you basically have to rely on your homes AC and dehumidfication because you are replacing hot humid air from the tank with hot humid air from the outside. Maybe geothermal cooling might help a little.

Just some ideas to toss around.

[Dag]

How long does your unit run on a hot day?

On a hot day it seems to run all the time.

When you had the condenser unit ( outdoor unit ) upgraded, was anything else done?

The furnace was also changed. The old furnace was the original unit from the 50's. I was expecting the A/C to work much better since the old furnace had a blower that was never designed to work with A/C.

No other changes.

Do you have ceiling fans?

Yes.

Something to consider is that the humid air will "feel" warmer and you will need to set your thermostat lower to compensate


On a summer day, it is difficult for the reach lower than 71 degrees, and on days when my wife is cooking and using the oven, impossible, and the temperature is usually about 74-76 inside.

Other things I tried in the summer: I covered the tank upstairs, but it wasn't airtight. I also turned off the fans to reduce evaporation. At one point I also reduced the speed of the fan blower.

Everyone says the tank shouldn't be the problem, but I know those lights put out alot of heat, and big tub of water at 80 degrees also creates heat.

I realize there are other factors such a window exposure, but it seems odd that my 2nd floor is fine, and with such a big unit on the first floor (4 tons) it can't cool it down.

Thanks for asking.

[capncapo]

If the unit size was increased and the ductwork was not changed, you may be limited by the size of the ductwork. If the ductwork isnt properly sized for the unit you won't be able to move enough air to keep the place cool.

Something that raises a question in my mind is how can your upstairs remain cool when all of the heat should be going up the staircase? Unless you have a door or someting else between the two levels it doesn't make sense as the cool air from the upstairs unit should be coming down the stairs as the hot air goes up.

I can understand the problem of it not being able to overcome the heat with the oven in use. That is fairly normal.

[Dag]

I was told by two senior HVAC designers that my duct work was big enough. Originally the whole house was heated and cooled by the original unit which used a 4 ton condenser. I reconfigured the system so that a separate unit was installed in the attic to cool the second floor. The supplies that fed the second floor were cut and turned to feed the first floor. When it came time to replace the original unit, we initially thought that we could downsize the first floor system to 3 tons, since we now had a separate system on the second floor. When the new 3 ton didn't seem to cool properly, I went back to the 4 ton.

It was shortly after the time of the change that the aquarium was added. So now I'm confused about what was cause and what was coincidence. It could be the tank has nothing to do with it all.

As for the second floor, there's no separation. That's the puzzling part.

Thanks for trying.

[nonot8946]

I wanted to edit my previous post to say that humid air is actually less dense than dry air and should rise.

[navajo]

Hey Cap'n,

I subscribed to this thread a few months ago for when I get my sump etc plumbed to the basement. I wanted to cut a vent in the cold air return in the fishroom.

Then the thread was brought back to life and I just re-read it again and noticed that most folks on here are talking about gas furnaces etc.

Will the vent mod work for a Heat Pump also?

thanks for your time and all the good info!

[capncapo]

Are you talking heating or cooling season?

It won't do anything during the heating season except spread the humidity throughout your house.

Should work fine during cooling season.

[navajo]

:lol: Guess that WOULD have been a good thing to include in my post huh?

I am more concerned about the Cooling Season. Since the winters are VERY dry around here and the summers are very humid.

We actually enjoy the added humidity from the 75 gal and 55 gal in the living room during the winter. Fewer nose bleeds. But I am about to put a 200 gal upstairs with about another 150 gal sump/fuge/etc in the basement and just don't want the mold to sneak in on me in the summer.

Sounds like a plan. Am going to pick up a vent tonight and see what I can break this weekend! :D

Take care and HAPPY NEW YEAR!

[capncapo]

Good luck and Happy New Year to you!

If you can't do the mod, you certainly won't be able to maintain a reef. It's a breeze.....

[Brad W]

I'm planning for about a 180g tank in my basement. How feasible would it be to basically seal the canopy over the tank and vent it with an exhaust fan out through an exterior wall? I realize this wouldn't be a true seal because of holes for electric cords and whatever cooling fans were being used to bring air into the canopy.

Since we live in Portland, OR we don't really have extreme temperatures. We leave the basement door open to the garage most of the time so the pooch can do what it wants. This makes me think I could probably vent air into the basement to combat any negative pressure issues without disrupting our comfort level or using a lot of extra heating/cooling energy.

This is new construction by the way, gas furnace and central air but we don't run either very hard. Sump will be in the garage.

[capncapo]

Should work fine provided that your fan and other equipment can survive the high temperatures and humidity..

[Whaledriver]

Brad W
Why not have a fan in and a fan out? They should balance each other out and limit the suction of air out of the house.

[Brad W]

Capncapo, is there a particular fan you would recommend that could handle the high temps and humidity? There will be about 20' of duct.

Whaledriver, your idea makes sense. I'd like to avoid running another duct if possible (and trying to locate it far enough from the output of the other fan) plus the additional large fan (more electricity, etc.). I was just hoping to use a few of those 4" icecap fans for air input and cooling in the canopy and then maybe just a passive vent on the exterior basement wall somewhere for the negative pressure thing. The ducting will actually be going through the basement wall and then through the garage's exterior wall. Your way definitely sounds more bulletproof though.

[capncapo]

Brad,

I've never had to look for such a beast. I'll look through some catalogues and see if there is anything available through any of my suppliers. You may want to do an internet search .

[Whaledriver]

Intead of the Icecap fans you might try some inexpensive computer case fans. Just have them go on and off with the lights and you should be fine.

[capncapo]

Evaporation occurs when the lights are off too

[Brad W]

That would be great if the canopy input fans only needed to be on with the lights. I'll be curious if I can get away with that for the big inline vent fan too.

[Brad W]

That's weird capncapo, we must have posted at almost the same time.

Yeah, I had a feeling you'd have something to say about evaporation even when the lights are off.

By the way, would there be much "passive" air exchange out the exterior vent w/o the inline fan on or maybe with just the canopy fans on?

[capncapo]

I'm sure that with ANY fan on you'll get a fair amont of air exchange. The greater the difference in temps., the better the flow. Canopy fans may be all that is needed at night.

If there is a HUGE temperature differential, you may get enough of a passive flow that no fan is necessary BUT you need to set the system up to take the greatest advantage of that. Your exhaust "stack" on the outside should be placed at least a few feet higher than the intake in order to get the airflow started and constantly moving in the right direction.

[causeofhim]

Interesting info. Thanks

[reeflover2]

Just a quick follow up question. I just moved into a new home and am planning on building about a 12' by 14' fish room. I was planning on using vapour barrier on the inside of the studded walls and sealing this to the floor and using a external steel door to basically eliminate this room from the house. My furnace is a 90% efficieny furnance which does not have a pilot and is pvc vented in and out. I also had the builder install two 4" dryer vents and the room also has a window. I am building a 84" x 72" x 30" tank. Reading your posts I have figured (I think) that my furnace will not remove humidity during the heating in the winter months. Is this correct? Will it remove the humidity when the air conditioner is running in the summer months? My house also has a cold air return in the fish room already. It is the cheap carboard thermal stuff that they use here. Would keeping this cold air return available during the air conditioning season help remove humidity from the room instead of using fans with the dryer ducts? My thoughts are to use this method of control in the summer months and use the two dryer vents in the cooler and winter months to cool the room and control humidity. I was thinking of running one of the dryer vents down to the basement floor and the other one install a good sized bathroom fan in the roof. Does this make sense? Would you also have a supply vent in the room for the cooling season as well to supply cool air into the room? Would you put it at the floor as well? Ay other ideas?

[capncapo]

Reeflover2,

The cold air return vent will help during the cooling season though I have reservations about the type of material from which it is made. The best advice that I can give you is to contact a local heating and cooling contractor and ask if there would be any problems associated with your vents and the humidity. My main concern would be mold growing on the inside of your return BUT I am not familiar enough with what you have to be certain about that. If it is what is commonly called "duct board", the material can develop mold in my environment in St. Louis but again, I am not aware of what possibilities exist when it is used in yours. How's that for a definite answer?:D

A supply vent would be a must if you are going to try to separate your fish room from the rest of your house.

Many 90% furnaces use the PVC in and out vents but many of the intake vents ARE NOT a requirement of the system and can be modified to pull the intake air from the home. You should be able to contact a local supplier of your particular furnace and ask them if the outside intake is in the design specs of the furnace and therefore is a must or if it can be converted to draw inside air. You will lose about 3% or 4% efficiency by doing this but you will also be sending some of your humidity down the drain as condensate.

Your 4" intake and exhaust vents should make a world of difference for you in the cooler and winter months.

As far as suggestions are concerned, I would need to know any information you can give me about your climate such as humidity levels in summer and anything else you think might help me.

[hawk66]

Are you familiar with a venting product called "Humidex"? To me it looks like an exhuast fan built into a verticle rectangular duct attached to an outside wall. It draws stale basement air near the floor and exhaust higher up on the wall. With this principle in mind I was thinking of diy'ing something similar in my fishroom by installing a bathroom fan near the floor instead of the ceiling and exhausting about 5ft up the wall. Does this make sense? Also is there a simple test to check for negative pressure. My gas water heater is located in my fishroom. I plan to either install a grill/vent on the fishroom door to draw from the rest of the basement or if this is not enough, install a fresh air intake in the fishroom and then seal the fishroom off from the rest of the house. Any thoughts you have will be appreciated.

[capncapo]

Hawk66,

I personally am not familiar with the Humidex product but fail to see the logic in its design. I would draw the air from the highest point possible as it is the warmest and therefore, most humid air in your fish room. I would think that removing the warmest, most moisture laden air would provide the greatest benefit when it comes to both temperature and humidity control. Removing the coolest air from near your floor will not help keep the wood in your floor joists or subfloor from absorbing the moisture contained in the hot humid air that will remain there.

A somewhat easy way to test for negative pressure would be to turn your fan on and hold something that produces smoke close to the flue pipe opening on your water heater. They draw air into the flue from the open space between the top of the heater and the flue pipe. If the smoke is blown away from the heater instead of being sucked up into ithe flue then you definitely have a negative pressure situation.

Personally, I think you would be ahead of the game by having the fresh air intake in your fish room and closing it off from the rest of the house. It will keep your house more comfortable in winter and will also help a bit with evaporation by reducing the temperature in your fish room. The cool air in the fish room can't hold as much moisture as the warm air from your house is capable of holding. I would place the intake as near to the floor as possible and the exhaust as near to the ceiling as possible. Not only will you be drawing the warmest air out but you may also reap some benefit from the natural convection.

[hawk66]

Capncapo, Makes sense, thanks for the info.
If your interested here is the link to the humidex site.
http://humidexatlantic.com/how_humidex_works

[hdtvguy]

<a href=showthread.php?s=&postid=6906852#post6906852 target=_blank>Originally posted</a> by capncapo
Hawk66,


A somewhat easy way to test for negative pressure would be to turn your fan on and hold something that produces smoke close to the flue pipe opening on your water heater. They draw air into the flue from the open space between the top of the heater and the flue pipe. If the smoke is blown away from the heater instead of being sucked up into ithe flue then you definitely have a negative pressure situation.



Is there a way to test for negative pressure other than using the flue on a hot water heater? I have an Electric hot water tank no flue to try this.

Thanks

[capncapo]

You could remove a short length of the flue pipe from the furnace and perform the same test.

[hdtvguy]

I have a Lennox Pulse HF furnace with the PVC flue and FA intake. Not sure the pipe can be taken apart?

[capncapo]

Negative pressure should not be an issue with that setup.

[hdtvguy]

okay thanks for the response.

[dgasmd]

I sincerely apologize in advance for replying to this thread before reading the entire thing. After having 2 larger tanks and set ups (360g tank/550g system and now a 750g tank/1000g system) I have come to what I believe is the best solution, long and short term, for humidity issues. Although I do live ina very hot climate all year round, I will include what to do for winters also for the folks living in the cold misery, I mean wonderful and gorgeous snowy, winters.

1. Isolate the entire system as much as posible fromt he rest of the house. I could not stress this enough. My current tank is inside the house now, but the only way it has ocntact with the air inside the house is via the air that gets drawn from inside the house to the above the tank area, which also gets fanned out to the garage where the equipment is. This is best for warm climates because you will be drawing cool air from inside the house above the tank where is hot and humid and blowing it in terms to the garage. For winter months, you may want to ahve a way to bypass the inside air going above the tank for air coming from the outside instead. Do the same for the filter or equipment room.

2. Cover your sump completely if at all possible!! Up until not too long ago, I was a huge fan of cooling with fans. I even have a huge fan blowing above the sump area. this causes a good amount of evaporation (10-12 gpd in my case) that can be replaced with cheap kalk and helps well with heat. The huge downside to this method is that you create an aweful large amount of humidity that settles in cooler surfaces (dew) causing a huge amount of rust and humidity damage. Even if you vent well the room where the equipment is, there will be significant humidity damage. Example is my own. I ahve all of my equipment in my garage, which remains open during the entire day for air exchange. If that is not sufficient air exchange,m I guess I don't know what is. Regardless, I close the garage doors during the night. In those 6-7 hours per night that the garage door remains closed, it has been enough to cause humidity damage to the wall behind the equipment and it has rusted every single thing that has even as much as a micron of metal in it. For somparision, a friend in similar climate and with all the equipment and tank in his garage has not a single sign of rust anywhere. The main difference is his sump is completely covered. He does not even open the garage doors, but does ahve a fan changing the volume of air in the room about 4-5 times per hour, which in my book is a far cry from leaving the doors opened completely. Most people with larger tanks will still require a chiller, as I and my friend do. In winter time, this is even worse as everything is cold and the humidity will settle on everything making it look like it rained isnide the house. I do believe the fan cooling has a place in the hobby, but it is most helpfull I think for smaller set ups or sets ups where the down sides have been addressed well and it prevents you from having to run a chiller at all.

Hope this is not repetitive to what already been posted.

[hawk66]

Dgasmd, I agree seperating the tank from the rest of the house seems the best approach. After many delays I have spent the past few day's doing just that for my new 375. Insulation for noise, vapour barrier,green board, and caulking all joints. I have installed a bathroom fan on the exterior wall about 2' from where the closest mh will be. I'll have 2 or 3 small fans at the opposite end/middle of the tank to ventilate some of the daytime heat. I also installed a ventilator fan thats contolled by a humidistat. I expect this to run 24/7 so I installed a fresh air intake ducted to the opposite end of the room as well. I will also install an adjustable vent in the door to see if I can draw from the basement as well. My gas water heater is in the fishroom, it needs to be replaced anyway so I'm changing it to electric to avoid negative pressure concerns.

[kwl1763]

SO here is my latest concern. I've done what I can so far. I have 2 cold air intakes above the tank (450G 10ft long), the tank itself is in it's own room that's walls, floor, ceiling, doors and stand are all heavily coated with marine waterproof bildge paint. I'm covering the 300G worth of sumps, chiller is outside and plumbed through the wall.


The last step I want to do is put a fan to draw air from the room to the outside using a humidistat. The only issue is that I'm in Atlanta. Many of you have heard it called Hotlanta which is really a misnomer. It should be called humidlanta! SO half the time the humidity outside will be at least as bad as the fish room.

My idea was to get 2 wired humidistats and plug them in parralell. One says if the inside gets above x then turn on, the other if the outside is below that x-10% turn on. That way the fan would not turn on unless the humidity outside was lower then the humidity inside.

1) Does that even make sense to do?

2) Is there a cheaper way? Those wired humidistats are like $200 each

[capncapo]

I'm sure that something like that would be possible but what you're going to try to do could prove to be a problem.

Something to consider is that 10% humidity at 90 degress is not the same as 10% humidity at 80 degrees. Warmer air can hold more moisture than air at a lower temperature.

If you could find a humidistat that will compensate for the temperature differential then your idea would have some merit.

[bbrantley]

capncapo,

If you're still up for it, I'd love your input on my humidity concerns. My environment is slightly different from some discussed here, and it may in fact be somewhat advantageous, but I'd like your take. I just posted to my young build thread describing my scenario, so I'll replicate it here for convenience:


Okay, I'm really ready now for some input on the ventilation in the room. Here are the relevant facts:

1. The tank and all supporting equipment will all be in one 200 square foot room.

2. The room has two windows to the outside and will be sealed off from the rest of the house with a weather-stripped door and moisture barriers behind all the walls, floor, and ceiling.

3. The room has radiant floor heating; there are no ventilation ducts anywhere in the house.

4. It's easy for me to cut holes in the side of the room that vent to the outside.

5. I live in a dry climate (Colorado) at 8,500 feet. It is consistently cold here in all but the summer months, and it is relatively cool in the summer -- never more than 80F and typically about 45F at night.


Given the above, what are my choices for managing heat and humidity? I've read about HRV's, simple exhausts, active air-conditioners, eco-coolers, bathroom fans, and more. It's a little overwhelming and kind of hard for me to understand what's really effective. My priorities are, in rough order, quiet, energy efficient, inexpensive, and easy to install.


Any thoughts from you or the group at large?

Thanks very much,

Ben

[Whaledriver]

You could get a fan controler that starts and stops a fan based on temperature and humidity

[capncapo]

Ben,

Having vents to the outside that would be manually opened, closed and adjusted when necessary would satisfy just about every one of your criteria and you didn't mention the word automatic.

Placing one of the vents low and the other high will make for a natural flow of air into and out of your room with no noise.

[bbrantley]

<a href=showthread.php?s=&postid=7727458#post7727458 target=_blank>Originally posted</a> by capncapo
Ben,

Having vents to the outside that would be manually opened, closed and adjusted when necessary would satisfy just about every one of your criteria and you didn't mention the word automatic.

Placing one of the vents low and the other high will make for a natural flow of air into and out of your room with no noise.

Thank you both for your replies -- I did forget "automatic," but not for lack of wanting. :)

This is what I was coming to suspect, but it's nice to hear my suspicions confirmed. Thanks.

Ben

[tye_c]

I am planning on installing an exhaust fan. Could I just Tee off the output to the return and to the outside? Then have manual shut offs on each? This way I can run the exhaust to the AC in the summer and winter and to the outside in the spring and fall.

[Whaledriver]

I wonder if any of the aquarium controller people can control a ventilation system? Instead of a chiller they can turn on a ventilation system?! Can you get a humidistat in these controller type systems?

[ellisz]

Ok, I am re-visiting this thread now that I have my 300+ system up and running. I have a 100 gal sump, 33 gal refugium and a 100 gal frag tank behind my 180 gal display. I have a 85 gpd dehumidifier that can get my humidity down to 43% but due to the settings on the unit, it has to run continuously. If I use a lower setting, it maintains 53%. Temps at 53% are 73 and temps at the 43% are 79.

I do have a return vent cut into my HVAC unit to help suck some of the humid air out. I also have a 4" vent fan that I use to blow air out of the house.

Would it help to cut another return? The room is about 10'x30' and is unfinished. I never really noticed a big difference after I cut the return in. I do keep my house fairly warm during the day so I wonder if my AC is not running enough? I can cut another return but due to the layout, it would be about 3-4ft from the other one unless I extended it with some flexible duct work.

Any ideas? I just want to keep the dehumidifier from running 24/7 and to keep the humidity to 45% or less.

[capncapo]

Installing another return vent could help but if the A/C doesn't run enough it may not help as much as you would like. Placement of the second vent is not critical. Just try to place it high so it is getting the warmest, most moisture laden air. Make sure that you put a closable vent on it just in case you decide that you need to draw more air from the other returns.

If your outdoor humidity levels are high then your vent fan could be working against you not to mention that you could be bringing in air that is warmer than what is already in your house. Either way, you should have a fresh air intake to prevent from creating a negative pressure situation and to allow the fan to work at its maximum potential.

Personally, I would run your A/C more during the day. At least you would be keeping the house cooler and reducing evaporation a bit. Your dehumidifier is costing you money to run and costing you money when your A/C has to run to cool the additional heat created by the dehumidifier.

[ellisz]

The sump room is in a unfinished part of my basement and the tank is in the basement as well. Temps are in the low 70's as it is now. I would be happy if the return would at least compliment the dehumidifier. I will go ahead an cut in another vent to see how it works.

Might even see about a new dehumidifier. I hate the fact that I can't dial in the humidity. I would be happy with 45% but I don't even know what the shut off on the high setting? The medium is apparantly 53%.

I have been considering putting up 2 walls to help contain the humidity and make the sump room smaller. I would have to put a vent in there as I am sure it would make the room hot with the dehumidifer in a smaller room.

[zachtos]

Any more ideas? I have the same problem now. 300G upstairs, 300G downstairs. I am now running a dehumidifier 65pt 24/7 and only able to maitain at 60% humidity, no lower. I am thinking of putting in a bathroom exhaust fan in the basement that vents outside controlled by a humidistat. I dont think I'll install a intake fan though, not sure what negative pressure will do yet either. I live in michigan, humid summers, dry winters, average fall/springs. Summer time was no issue because the AC ran all the time (which it still felt very humid in my house 1100sqft not including bsmt) I am going to try covering the sumps today, hopefully the tank wont get too hot... but I HAVE TO find something, the floors are starting to warp, the doors wont close in my house... it's a very big problem and it could cause me to have to shut the $10K + system down!!!

[FishTruck]

Hi Zack. Wathching your build with great interest. Here is what I am planning for my tank. The idea was stolen from Hop. Basically, I have a sealed hood over my tank, and a sealed cabinet around my equipment. I am going to vent the system with outside air, totally isolated from the house. I also have a big dehumidifier in my basement, but, want this running as little as possible.

Managing the system during extremes of outside temps and humidity will be the challenge.... but since it is isolated from the house... I really only need to worry about the temp of the system and lights.

Ryan.

http://i42.photobucket.com/albums/e314/rmanecke/th_TankVent3.jpg (http://i42.photobucket.com/albums/e314/rmanecke/TankVent3.jpg)

[capncapo]

Zack,

You might want to look into an HRV if you want to retain the heat.

If you don't, a ventilation fan with a fresh air intake will do you good. Negative pressure could become an issue unless you have an electric hot water heater or a furnace that doesn't use a normal flue ( something like a pressure vented unit that has a fresh air intake ). The fresh air will do your system good as it will help to keep CO2 levels low which will help keep your pH stable.

[jnarowe]

Check my web site for how I deal with this. I agree with dgasmd
that salt/humidity damage can be a pain. I fully isolated my tank room from the rest of the house and installed an exhaust fan pulling air from above the tank and venting it outside. The return air is an open attic style vent under my deck which allows cool air to replace the exhausted air.

I also installed a temp. & humidity controller on the exhaust fan but ran into trouble because being in the NW, the outside air is sometimes more humid than the tank room air. So what happened is the humidistat was cycling the exhaust fan all day and night. I just turned off that part of the controller.

It can get humid in the tank room so I occasssionally adjust the temp setting. The big mistake was that I installed stainless work tables and a refrigerator in the tank room, and they will oxidize fairly easily. When I go to remodel the tank room, I will pull out the SS stuff and replace it with laminated wood.

Anyway, I find this method to work well considering how cheap it is to run. I do cool my system with blowers and that does cause the humidity to jump as stated earlier, but I can live with that. I also painted the walls and ceiling with yacht bilge paint, so there is no issue there.

[bguile]

I'm hoping I can get some assistance in this thread from the HVAC expert. Here's a pic of what I'm working with:
http://i156.photobucket.com/albums/t38/dukeintl/Aquarium/A630-070613-0507.jpg
http://i156.photobucket.com/albums/t38/dukeintl/Aquarium/A630-071010-0937.jpg
If you look closely, you can see that there is a duct feeding a/c and heat to the living area upstairs. Can/should I able to cut out a section and add a register for helping to cool the tank area during the summer months?

I am also planning on adding a bathroom type vent in the ceiling that will vent outside which is just a few feet to the left, will doing these two things be an issue for negative pressure? If so, how is it different from having this same type setup (vent and fan) in a bathroom. I'm all confused on this negative pressure stuff.

BTW, the dimensions of my area are 6'x6'x8'. The tank will be enclosed in a wall but not totally sealed off from the rest of the house. I plan to install a louvered door to access the room which is off what will later be my office.

This is the view from the front and back.


The blue floor area is what will be the equipment room.

Thanks.

[Whaledriver]

It seems to me that making use of household air can only lead to problems. You have humidity, smell and rust issues. Even if the outside air is warm the air in the hood is always over a hundred with the lights on so any new air should cool. With high enough airflow the evaporation should effect should help cool more.

My ideal system would have a variable speed fan controller that would speed up until the exit air hits a set point.

The second part would have a heat recovery system to use the heat from the exit air to warm the house in winter

[bguile]

<a href=showthread.php?s=&postid=11100959#post11100959 target=_blank>Originally posted</a> by Whaledriver
It seems to me that making use of household air can only lead to problems.

How so? We dont setup isolation systems for smaller tanks, say 120G, so that none of the "house" air moves about the tank. In fact, most of the time that same air is being used by fans and the like to help keep the water cool via evaportation. Why would it be different because I'm putting the tank behind a wall?

<a href=showthread.php?s=&postid=11100959#post11100959 target=_blank>Originally posted</a> by Whaledriver
Even if the outside air is warm the air in the hood is always over a hundred with the lights on so any new air should cool. With high enough airflow the evaporation should effect should help cool more.

So are you saying that maybe I could install an air vent or something to the outside to allow cool air in the room in the winter months?

[Whaledriver]

The more tanks you have the more smell that happens. You might not notice it but aquariums add a smell to a house. Ask someone who visits. Most of the time its not bad but it is a smell none the less. Smell your skimmer cup?

A heat recovery air to air exchanger will allow you to use the heat in the winter.

If you have a lot of tanks the humidity becomes a major issue so having the hood air separated from the room also prevents this. I have read a lot of threads about rust an mildew to ignore it. With a bright lighting system you can loose 3% a day to evaporation. With a 1000 gallon tank system that's 30 gallons a day in a 22 x 22 basement a DAY!

The design I have planed but not built is similar to FishTruck but I would run 2 ducts behind the tanks to feed new air and exhaust air. The system would have air tight hoods to separate all the air from the room. Matching intake and exhaust fans should keep the air pressure neutral.

[jnarowe]

I have a 1000g tank with 1000W lamps and it only evaps about 12g/day. But, rust is still an issue. I have stainless tables in my tank room and they rust up. Mold is not an issue in my case, but if my tank were open in my house, it would be a serious issue for sure.

[bguile]

<a href=showthread.php?s=&postid=11106142#post11106142 target=_blank>Originally posted</a> by Whaledriver
With a 1000 gallon tank system that's 30 gallons a day in a 22 x 22 basement a DAY!

Well it's a good thing I only have a 210 then and my plan is for the air to be taken OUT of the tank room to the outside, not blow it back into the house. So again, I don't see how drawing air from the rest of the living space INTO the tank room and out through a vent fan is a bad thing. I understand moisture in the air being a bad thing and cause for rust and the like, but I'm not blowing it into the living area.

[capncapo]

Drawing air from the house is not necessarily a bad thing but not necessarily the best thing. CO2 levels in the home can influence your pH in a negative way.

In order to exhaust any given amount of air you must intake the very same given amount of air from somewhere otherwise you would be living in a vacuum.

Negative pressure results from blowing air out of the house that is not replenished by air leaking through cracks and crevices, open windows or doors or other types of "leakage" to the outside. When that happens, air is brought into the house via the "path of least resistance" which is typically DOWN your flue in homes with furnaces that are NOT electric or rated as being 90% efficient OR homes with a gas water heater ( unless power vented). If your gas furnace or hot water heater happens to be running then potentially dangerous exhaust gases are brought back into the house instead of being harmlessly exhausted up your flue. Not a desirable situation, I'm sure you'll agree.

If you have an electric furnace and water heater then flue gases are not a problem. Gas furnaces that are rated as 90% efficient typically have a "flue" made of PVC ard are power vented to the outside and the chance of a negative pressure situation bringing the exhaust gases back into your home are practically non-existent.

If your home can't leak 100 cfm of air then you can't vent 100 cfm of air without some kind of a fresh air intake. If it happens to be very cold or very hot then you are working against your furnace or air conditioner by allowing air to "leak" into your home. It's best to let the air "leak" into the room where it is desired and will do the most good thus keeping the rest of your home more comfortable.

There is NO single solution to keeping humidity at bay unless you never have rain, excessive heat or cold. The solutions are dependent upon the climate in your area, the seasons of the year and even the weather on any given day. What works in one area of the country WILL NOT work in another area of the country unless the climates are identical.

Venting light hoods that are part of a "closed system" may keep your lights cooler but does NOTHING as far as removing humidity from your home except for possibly keeping temperatures down in your room. The cooler the temp of the air in your room, the less moisture it is capable of holding...i.e. the moisture content of the air in a room with 80% humidity at 70 degrees is less than the moisture content of the air in a room with 80% humidity at 90 degrees.

[bguile]

Now that entire explanation makes sense to me. Thanks for chiming in. I believe I do have the 90% efficient utilities you spoke of.
This is a pic of the water heater. The vent goes through pvc to the outside of the house on the side.
http://i156.photobucket.com/albums/t38/dukeintl/Aquarium/A80-071103-0002.jpg

This is the furnace and the vent outside the house.
http://i156.photobucket.com/albums/t38/dukeintl/Aquarium/A80-071103-0003.jpg
http://i156.photobucket.com/albums/t38/dukeintl/Aquarium/A80-071103-0004.jpg

So on your point of replacing exhausted air. Seeing that the wall to the left and just above the tank is to the outside, I was thinking of creating some type of opening that I can open in the winter time to help cool the room and close in the summer to pull more of the cool air from the house. Not quite a window, but an opening that would be a "least resistant path". I was thinking of a screened opening attached to vent shaft with a closeable register or something of sorts. Will this work? Do you have any low cost suggestions?

[siropa]

I was thinking of doing an opening similar to bguile. I was going to use one of the standard air intake pieces found at a home improvement store for the outside and put a duct baffle on the inside to close it off.

capncapo, my question is: would it be better to put this intake right into the fish room as is, or run that duct into the cold air return for the whole house?

[capncapo]

Anything that is weatherproof and can be closed or capped off will work fine. That can include PVC, aluminum, galvanized metal or anything else you might think of.

I think you'll find more air exhaust items at your local hardware store than you will intake items. Most will have some sort of flapper that requires air blowing out in order for the flapper to open. You can always remove the flapper but try to insure that animals and bugs don't have a path into your home if you do.

Personally, I would have the fresh air intake in your fish room if you have a fish room. I would also run it down close to the floor.

If you will be venting the hot air out through the same wall I would place the intake and exhaust as far apart as possible. You don't want to exhaust hot, moist air and then turn around and suck it right back in.

[siropa]

Thanks a lot for the info capncapo.

[capncapo]

NO problem siropa.....that's what I live for.:D

[jnarowe]

I did a 6" exhaust and a 12" x 14" open attic vent. The vent goes through the tank room wall and is exposed to the outside air under my deck. This affords me cooler air during the Summer, and the exhaust fan is cycled by tank room temperature. I can't use teh humidistat because sometimes it's very humid outside here.

[tinmanny]

skippyreef here are some ideas and sugestions from a licensed sheet metal worker who also happins to run the apprentice training program in the state of RI

negative air is caused by removing more than replaced it genraly takes a very strong fan to do this

I would not ever run air from your fish room to your furnace because it will cause rust and corrosion in the unit and that can be very expensive and dangerous you will rust the heat exchanger and let carbon monoxide into the house

I would guess that the pipe I saw in one of the pictures going to the furnace area is a freash air or possible combustion air because some units consume a lot of air and can starve and do a poor job of heating when that happens

all you have to do to lower the humidity in your fish room is steel heated or cooled air from other areas and the you will acomplish two things
#1 figure what size the room is in sq ft length x width that is the amount of air you want to move
once you know that figure get a 2 speed fan high being the one you shoot for in fan capicity example 10 x10 room = 100cfm fan on high should do just over 100cfms low being the seasons when the water evap is lower
#2 use a basement window to vent the fan with a dryer vent they come in all sizes lows may have them but any heating supply store will carry them use the size on the fan
then get 2 of the same registers to accomidate the cfms you calculated and install them in the wall across from the exaust fan and the air will exchange with house air that is low in humidity and at the same temp as the house
by doing this you have exausted the air with all the water in it and you replace it with good dryer air at a rate equil to the size of the room at a medium to high rate depending on the speed you choose and your house will thank you for it and your furnace will suffer no ill affects

Good luck
Manny :smokin:

[FishTruck]

OK. Strap on your jocks and see if you can follow me through this one! :D

Review issues with a "closed" system vented in and out from the outside. I am answering my own questions here, but, I am not sure if I am correct. This is Chicago land with all extremes of temp and humidity.

I am planning a sealed headspace above the tank and above my sump. Both exhausting outside and aspirating outside air. Both as close to "air tight" as possible. I will keep the skimmer outside of the sealed area, so that the water will be aereated by skimmer action with constant house air.

http://i42.photobucket.com/albums/e314/rmanecke/th_sealedsumpvent.jpg (http://i42.photobucket.com/albums/e314/rmanecke/sealedsumpvent.jpg)


Ideal spring and fall. Cool air with reasonably low humidity will ventillate the system, keeping it cool, but not too cool, and venting humidity out of the canopy and the equipment room. Could be controlled to keep the air above the tank below 80 degrees.

1. Extreme Winter. Cold dry air will be coming in which will cool the tank nicely. But, because the cold air cannot hold much water, and there will be a limit to how much I can vent in before the tank starts to get cold. So, the potential problem is a 100% humidity situation above the tank and in the equipment room. Is this a problem?

Also, if it is really cold, there will possibly be very little ventillation.
This could cause CO2 accumulation if the system is really sealed from the house. Could this be counteracted by keeping the skimmer outside of the sealed area?

And... in the winter I could set the above canopy temp to a lower setting to encourage more ventillation. Using heaters to keep the water temp constant.

2. Summer. Hot humid air will be coming in. If it is 90 degrees outside with high humidity, the fan will run constantly, and might not be able to keep the tank temperature down. Hello chiller. I guess as long as the lights don't overheat, this would be o.k., just sucking up lots of electricity.

For a 300 gallon tank, and 180 gallon sump, I am planning a single 120 cfm fan. Maybe I should have two of them with independant temp control? One for the sump, one for the tank? I can start with one and upgrade as needed.

Thanks for any comments.

My tank arrives friday.

:eek:

[tinmanny]

what happins when it rains for two days

[tinmanny]

what happins when it rains for two days

[tinmanny]

just use house air for supply it is already the best for the situation and when you get it too damp it is out

[FishTruck]

Well, if it rains for two days straight, I will be venting the tank with humid air. This will keep the lights cool and fresh air over the water, it will just be high humidity. I guess the tank lights can handle that without corrosion problems? It will be isolated from the house anyway.

As backup, I do have the system set up to vent with inside air if I need to from time to time. I could even automate this with another fan and some louvers.

Regarding venting with house air and exhausting outside...
My water heater and furnace have open flus... so I have to avoid negative pressure in the basement.

[Whaledriver]

FishTruck
The winter air can be your friend because it is so dry. The key is letting the lights warm the air to the point it can carry away a lot more humidity than in the summer. Another benefit is that in the winter you can use the heat for your house if you set things up right with a heat exchanger. In the summer your last resort is to turn off some lights if temps get to high.

The ideal system would have intake/exhaust fans that can be slowed down depending on the needs of the seasons. My best cheap way would be a pair of 3 speed fans and a 3 speed controller. This would allow you to control the exhaust temp in the winter to keep it from going to low in he winter. In the summer you should be able to cool the tank to the point. Beyond this point you could then have some of the lights go off to lower the heat input. At a certain point when the temps over 95 or 100 you might have to open the tank to your inside air to keep things alive. This could be a simple servo to open the ducting system to the inside air and close it off to the outside air.

This is easier to plan and blog about than to actually do. If I ever get to the point of remodeling my basement I will find out if it works. Hopefully by then a controller computer will be cheap and helpful enough to monitor and control the parameters in all the sasons

[Nanook]

HRV for winter months may be necessary if you lose too much heat, or simply using exhaust fan with fresh air intake if losing heat is not an issue.

Air conditioning the room via a window unit or split AC would be better for humidity removal and temperature control in the summer months.

[FishTruck]

Thanks guys! This helps. I think this is going to work!

I will have an AC3 controller programmed to to cut the lights in heat emergencies. This will also control the ventillation fan.

I have a 100 pint per day dehumidifier in the basement for backup. Will look into an HRV unit.

The good thing, is that I have the winter to just run the plumbing and cure some rock and see how the temp control and humidity work out.

Will start a post to log my trials and errors with this.

Ryan.

[bguile]

<a href=showthread.php?s=&postid=11108592#post11108592 target=_blank>Originally posted</a> by capncapo
Anything that is weatherproof and can be closed or capped off will work fine. That can include PVC, aluminum, galvanized metal or anything else you might think of.

I think you'll find more air exhaust items at your local hardware store than you will intake items. Most will have some sort of flapper that requires air blowing out in order for the flapper to open. You can always remove the flapper but try to insure that animals and bugs don't have a path into your home if you do.

Personally, I would have the fresh air intake in your fish room if you have a fish room. I would also run it down close to the floor.

If you will be venting the hot air out through the same wall I would place the intake and exhaust as far apart as possible. You don't want to exhaust hot, moist air and then turn around and suck it right back in.

I'd like to say thanks also. I thought it could be implemented but wanted to put it past an expert for critique.

[jnarowe]

And the bugs can be a problem. My inbound vent gets covered with them and I have to shop-vac them off. I guess they are attracted to 1000W 20K lamps!! :lol:

[bbrantley]

It sounds like you are on the right path.

I use a pair of fans plus a humidity and temperature controller to trigger them for air exchange in my fish room. I happen to live in a place where the outside air is always cooler and drier than my tank's water temp (80F), which means passive cooling and air exchange are both viable.

During the daytime in the winter, the tank lights and solar flux keep the tank room above 80F with no active heating, which means the tank water stays warm without any extra heating, too. A few times during the day the fans will kick on and bring in cool, dry air while purging the wet stuff. At night the room drops as low as 65F and the heaters kick in. I set the controller to keep the room humidity at 70% or better.

In the summer, the room can get considerably warmer, so the fans will stay on much longer, and I must allow the room humidity to get higher, too. There is plenty of cool night-time interval, though, to let things stabilize and "dry back out" in time for the next day's round of warming up.

Since you have a nice chunk of time to "practice" with environmentals, try the passive routes first. They are cheaper, more energy efficient, and there are less things to "break." If your controller permits it, put an extra sensor in the room to measure the ambient temp and collect some data. You can use this to "tune" your choice of equipment. Do recognize, though, that the real challenge will probably be in the summertime unless you live in a cold climate.

Good luck!

Ben

[wmilas]

I'm the the process of planing out an inwall 7x3(or 4)x2.5 tank for the basement. Some particulars:

* I bought a new builders spec house on the cheap. The HVAC system was ripped out and redone.
* I live in Chicago so its both humid in the summer and cold/dry in the winter.
* I have a 90+ variable speed lenox in the basement that services basement and first floor.
* I have an 80 variable in the attic that services the second floor. the reason its not a power vent is because its in an uninsulated part of the attic.
* Both condensors outside are variable speed, and the controlers can lower them to draw more humidity out of the air in the summer basd on the humidistats and the outside temperature sensors.
* The system monitors the dew point and kicks on the humidifier in the winter to keep humidity just under where the windows dew up based on outside humidity. Furnaces circulate air wheter burner is on or not to spread humidity if humidifier is running.
* HRV runs during the winter and most of the summer (I turn it off spring and fall when the windows open)
* Both systems have large canister hepa filters. Furnaces are the 4 inch media filters. Hepas run 24x7.
* Waterheater is a powervent, and its next to the furnace in the basement.

As you can see I take my HVAC seriously :) Its the best system I could put together energy effeciency wise that still made "sense" It helps that my cousin-in-law is a HVAC contractor :)

I'm REALLY happy with it.. the variable speed means its always comfortable, its always the right humidity, its always, well nice. I don't want to completely screw this up with the tank going in :)

So this was what I was thinking after reading as much as I can:

* Seal off the fish room.
* Install a HRV fishroom only.
* Install a dehumidifier. I have a lil portable jobbie put I'll probably look for something maybe a bit larger and more efficient.
* Install a small dedicated AC system with a condenser outside.

How it would work
Summer:

Run the dehumidfier on a controller over 60%. Run the ac system keep room at 78ish. Temp sensor and humidi sensor installed outside. If at night temp falls below say 74, HRV kicks on and runs. Obviously the settings need to be tweaked but you get the general idea. Keep it as energy efficient as possible. I'm toying with the idea of adding a simple non HRV vent with a outside return to capitalize on the cool summer air.

Question: any way possible to hook a chiller into the outside condenser to make this even more efficient?

Winter:

Air return in fish room opened up so that humidity can be circulated in house. Manual system or humidity control actuater. If it screws up with the dewpoint calculations of the whole house system I'll just leave it closed. Will need to plumb in a fresh air vent to the rest of the basement for pressure to equalize so the return works. this is midly complicated and I have reservations about it. All I gain out of it is "free" humid air, and the current system actually does a good job of that. I also risk taking in nano-sized salt crystals and rusting the hell out of the HVAC gear.

Same setup above with summer although obviously the AC should never run unless something goes horribly wrong. The HRV and the dehumidifier should be able to hand the load. I assume I do want a HRV... being in Chicago when its -10F I'm thinking humidity and not heat are going to be the issue.

Am I missing anything here?

Thanks for your time :)

[Oldtimer]

wmilas

I've been following this thread because I'm also in he process of planning in a large basement tank. I live in more or less the same climate as you (suburb of Detroit) and have similar plans. My current HVAC system is far from being as up to date as yours. It's a 25+ yr old system in a 1937 home. Suffice to say that it's in need for an upgrade, so I'm trying to plan my new HVAC system in conjunction with the tank.

My install shares one significant difference in that the tank will be an open top braceless design (~225gal) located in the living area of the basement ~10 feet from the equipment room. So, my approach is to focus on conditioning the air not only in the equipment room, but also the living space of the basement. I'll probably install registers above the tank in the ceiling to extract the air away from the tank either into the equipment room or directly through an HRV installed in the equipment room window. My basic idea is to suck humid air out of the area around the tank and the equipment room and process it through an HRV (geared towards the cooler/dry months). I'd also ike to maintain flow through the equipment room in order to avoid pH swings. Managing all this seems like quite a task, but I'm fortunate enough that my next door neighbor is a Sr. HVAC Tech at York. It's a good thing he appreciates beer! ;)

I'm also thinking about installing a second A/C unit to focus purely on the equipment room. Although, it would likely only be needed during the June-Aug months when outside temp/humidity peaks. I'd prefer to go this route only in lieu of a chiller. I like the idea of dumping the chiller's heat outside though. Perhaps that would eliminate the need for a dedicated A/C unit. I'll have to dig into this option.

I also share your concerns with rusting out the HVAC system. At least using a dedicated system (HRV, second A/C unit, blowers, etc) offers some piece of mind for your main HVAC equipment.

It seems that there's about a million different ways to setup a system like this. So far, I've been seriously researching this for a few weeks and have learned more about residential HVAC than I ever would have dreamed to know. This thread has been very helpful in pulling together a lot of good info.

One other item I've come across is an ERV (Energy Recovery Ventilator). It's basically an HRV with a built in dessicant wheel or other form of removing moisture from one air stream and transferring it elsewhere. It's mainly targeted for warm/humid climates, but I think it has it's value in our hobby. Here's a quote from the following link...

"The most popular design of ERVs utilizes a desiccant
wheel to remove both heat and a significant amount
of moisture from the incoming air, which reduces the load
on the air-conditioning system."

http://www.advancedenergy.org/buildings/knowledge_library/ventilation/erv.pdf

I'm not sure how effective these units are, but they caught my eye. If they reduce the overall burden on an A/C system, that should translate into lower energy bills.

[wmilas]

Oltimer:

From the research I have done it seems that the dessicant wheel in the ERV saturates pretty fast and is not suitable for the amount of liquid generated by a tank. The thing is I know of no one who actually has one so its hard to tell. Since we are in the northern climates none of the contractors up here have any experience with them so I can't get a straight answer out of anyone.

As far as a chiller vs an airconditioner I'm just as stuck. If I install a chiller and a dehumidifier, and then make sure the tank has a closed hood on it in the fish room, along with sealing up the sumps as much as possible, I may not actually need a AC unit. My gut tells me I will though in the summer, then we are back to do I use the house airconditioner and risk the salt damage, or put in a smaller dedicated unit that I can blow up :)

I was initially toying with an opentop design but having that much humidity in my basement scares me :(

[jnarowe]

What about using a ground loop to keep your tank cool and save some energy?

[steve the plumb]

I have a dehumidifier but at this time of the month it doesn't go on.It did go on two weeks ago(just bought it recently) and it does heat up the room.I still think an a/c unit is better to dry the room and cool it.I have 2 portable a/c units I think I will install one in the garage and the other in my basement.My tank is covered for now but I also haven't installed my lighting.Once the lights go on the heat will rise.I do see this being a problem in the summer.I also see it as a waste to cool my garage with an a/c unit in the summer(sump is in the garage)I was wondering if I installed a fan to push the hot air out(garage) would that be enough,and left an a/c unit in my basement where the tank is.

[steve the plumb]

wmilas you have pretty much a similar climate as we do.It may get more humid here(75%-95%) in summer and it does get hot.My old 150 was in my basement as well but my sump was underneath the stand.I had most of the top opened and I had to have my portable A/C unit on all summer or the tank would get to hot on those warm humid days.The problem with a chiller is if the room is to hot its not as efficient.I think the dehumidifier will drive the temp to high.I have seen my room temp go up to 25 celcius when the thing is on.Unless you can vent the heat outside you will be heating the room to get it dry you are better off with an A/C unit European models are nice I regret not getting one for my basement instead I have to install my portable one in the summer.