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kcrush4989
10/16/2016, 10:14 AM
I'm in the planning stages of setting up a 1500-800g system and an looking for the best way to heat it. There are several inline heaters that range all over the board for price. Need some input on how you guys heat your tanks

rygar
10/16/2016, 10:20 AM
Have you looked into a closed loop to the water heater using pump and Ranco control unit?
100' pex line coiled in the sump looped to the water heater. When water drops below the set point, a pump sends water from the water heater, thru a closed loop thru the coils thereby heating the water. It's not the easiest thing to set up, so if you know a good heating and cooling guy, would definitely have him at least make the connections.

Achilles Torben
10/16/2016, 10:28 AM
HQI lights and you don't need a heater.

Gre Torben

Gesendet mit Tapatalk

sfsuphysics
10/16/2016, 11:22 AM
how is the cost of electricity vs. cost of gas in your area?

If you're heating your house & water with electricity just use heaters in the sump, no sense getting fancy with in-line and what not, just heaters in a good flow area of your sump should be fine.

dave.m
10/16/2016, 12:33 PM
Get multiple electric heaters of lower wattage instead of one great big one so that if one sticks in the ON position it won't fry your tank.

Dave.M

sfsuphysics
10/16/2016, 02:36 PM
Get multiple electric heaters of lower wattage instead of one great big one so that when one sticks in the ON position it won't fry your tank.


Fixed it.

dave.m
10/16/2016, 03:39 PM
:thumbsup:

Dave.M

rygar
10/16/2016, 06:43 PM
Fixed it.

Exactly...that's the only reason I went with the closed loop to the water heater. Peace of mind is a huge factor with planning a big reef tank. And aren't monster plug in heaters crazy expensive? For 1500 gallons of water, you'd need 4500 watts of heat right? I could be wrong, but I think it's 3 times water volume for heaters. So divide 4500 x 500 and that means you'd need nine in line 500 watt heaters.

skanderson
10/16/2016, 10:07 PM
I would agree that the way to heat a large tank is to use 400 watt mh lights. the main drawback to mhs is the heat output, and for a northern tank like mine that is only a drawback for about 3 months and a perk for about 6.

kcrush4989
10/16/2016, 10:09 PM
Thanks everyone for the help. I want to stay away from the (many) plug in heaters. I would need a ton. I'm interested in using my hot water tank and a coil. I'm a contractor by trade and can solder in what's needed. Can any post a pic of there setup?

Thanks

sfsuphysics
10/17/2016, 12:52 PM
Exactly...that's the only reason I went with the closed loop to the water heater. Peace of mind is a huge factor with planning a big reef tank. And aren't monster plug in heaters crazy expensive? For 1500 gallons of water, you'd need 4500 watts of heat right? I could be wrong, but I think it's 3 times water volume for heaters. So divide 4500 x 500 and that means you'd need nine in line 500 watt heaters.

Well there was a reason why I asked about cost of gas vs electricity, I'm sure I can easily look up those rates for Buffalo, NY but hey it's not my tank :D Some areas have crazy low electrical rates (at least compared to what I pay), and some areas do not have natural gas availability and I've heard propane isn't cheap which is why I didn't suggest tying into a gas water heater (needs to be gas to have any chance of being useful, electrical water heater you might as well put heaters in your tank).

As to how many heaters are needed, it's a little more than just gallons. I forget what was told to me some 10+ years ago, but it was something like 1 watt per gallon per 5 degrees below ambient temperature. So if the room with the tanks is 60 degrees, that's 1500g x 1 x 4 (80-60=20 then divide by 5 = 4). So if you had all the inner workings of the tank inside an uninsulated garage, get ready to pay through the nose during the winter months, heck here in San Francisco I get hit fairly hard for ambient temps in the 50s.

Another option is to insulate a fish area behind it, and physically keep that warm with your furnance/boiler/etc, again unsure about gas prices, but around here stores tend to keep themselves warm rather than rely on electric heaters to keep their tanks warm. Now the downside to this approach is you'll more likely than not be fighting the humidity too, so some sort of heat exchanger that saves some the heat while evacuating the moisture is a must with a tank that size.

Mishri
10/17/2016, 03:43 PM
Anyone ever use a Heat Pump? I read someone using one a while back.. I did some searching and it looks like it's a chiller/heater all in one... seems like it might be a good solution as in the winter I let my house get down to 64 degrees, and in the summer it gets in the mid 80s (few days in the upper 80s)..

Vanpire
10/17/2016, 04:48 PM
I would agree that the way to heat a large tank is to use 400 watt mh lights. the main drawback to mhs is the heat output, and for a northern tank like mine that is only a drawback for about 3 months and a perk for about 6.

Is the other 3 months - no net benefit or drawbacks?

rygar
10/17/2016, 06:02 PM
Thanks everyone for the help. I want to stay away from the (many) plug in heaters. I would need a ton. I'm interested in using my hot water tank and a coil. I'm a contractor by trade and can solder in what's needed. Can any post a pic of there setup?

Thanks

I'll see about getting you some pictures. I absolutely love heating my tank this way. Previous 560 reef was heated with a couple large titanium heaters, both failed. One failed on...replaced it...then one failed off...so replaced that. Caught both in time.
A friend of mine just lost a tank full of corals due to a failed heater.
Current system is 1200 total gallons and no worries whatsoever. But ya never know so despite it most likely will never happen, I'll probably get a shutoff control as a fail safe in case for some reason the pump or controller fails.

rygar
10/17/2016, 06:21 PM
Can't get my photobucket to download my pictures. I'll keep trying.

Mike Hart
10/17/2016, 06:24 PM
I have a titanium inline heater on my 600 gal and it runs flawless....On a system of this size I wouldn't go any other way

Mike Hart
10/17/2016, 06:31 PM
I have a titanium inline heater on my 600 gal and it runs flawless....On a system of this size I wouldn't go any other way

dave.m
10/17/2016, 10:35 PM
Can't get my photobucket to download my pictures.

In Photobucket, select the Direct URL for the photo you want. and copy this.

In RC's Edit window, select the yellow mountain icon. A pop-up box will appear saying http:// in boue.

Paste your PB URL in the box.

Dave.M

kcrush4989
10/18/2016, 06:36 PM
Gas in my area is pretty cheap so I would like to run off my hot water tank. I would like to see how this is done and any precautions that should be taken. Fail safes? My grow out tank and dumps will be roughly 12 ft from my hat water tank.

Will F
10/19/2016, 01:30 PM
Looking to do the exact same thing. Its quiet easy. Your really just creating a zone off of the water heater. This is similar to how your typical heating system opperates. In your tank is a temp sensor, it tells the circulator/ zone valve when heat is required. Then water is directed from the water heater to the coil of PEX in your sump.

Will

skanderson
10/19/2016, 04:04 PM
yes about 3 months max where the house is closed up and the heat is not wanted, about 6 months where the heat helps keep the tank and the house comfortable, and a few months where there is no benefit or drawback.

kcrush4989
10/19/2016, 04:23 PM
Looking to do the exact same thing. Its quiet easy. Your really just creating a zone off of the water heater. This is similar to how your typical heating system opperates. In your tank is a temp sensor, it tells the circulator/ zone valve when heat is required. Then water is directed from the water heater to the coil of PEX in your sump.

Will

Are there literally zone valves like on a boiler that can be used? I'm afraid of back feed when showering or anything like that? I get the concept and like it. Just want to make sure waters doesent circulate when not needed.

sfsuphysics
10/19/2016, 08:31 PM
Are there literally zone valves like on a boiler that can be used? I'm afraid of back feed when showering or anything like that? I get the concept and like it. Just want to make sure waters doesent circulate when not needed.

1- you can buy a pump that pushes water, get one designed for this not an off the shelf aquarium pump, they're not cheap but they are rated to handle the pressure that you'll have in your pipes.

2- you can get check valves to make sure water only goes one way

There might be some slow drift of heated water simply due to thermodynamics, but overall if you set up your system correctly you should be good to go. If you add a heat exchanger and have a closed loop on the heating side then no worried about water moving when you turn on a shower or anything, although not sure that it would anyways.

Will F
10/20/2016, 10:41 AM
Are there literally zone valves like on a boiler that can be used? I'm afraid of back feed when showering or anything like that? I get the concept and like it. Just want to make sure waters doesent circulate when not needed.

Yes zone valves like on a boiler. The system is a closed loop system so there is no real concern that water is back fed while in the shower. The only real risk I can think of is if the "heat exchanger" (pex coil) was to fail or leak you would end up with a fresh water leak.

The system opperates like a std heat system. Like in the home. When your living area is calling for heat the zone valve/circulator turns on and curculates hot water to radiators. This heats up the space. The pex coil is doing the same but instead of heating the space via air it is heating the water via the coil.

Hope this helps.

Will

fishguy306
10/24/2016, 09:39 PM
You guys using the water heater loop, I'm attempting to set one up now, for the life of me I can't get it to stop leaking where it connects to the drain on the heater. It has garden hose threads, I found a piece that converts to NPT on the other side and can get rid of the leaks there, but no luck on the drain valve. I've tried with and without thread sealant. It has the gasket in it but it keeps popping out of placewwheni screw the fitting on.

sfsuphysics
10/25/2016, 12:21 AM
Why are you connecting to your drain valve on your water heater?

If you're doing an open loop, you connect to the exiting hot water to go to your tank, then the return connects to the incoming cool water. With a pump of course.

fishguy306
10/25/2016, 09:43 AM
To be honest that is the only way I had seen it done. The three or four I've seen build threads for all went back in the drain valve. I guess it was so you don't get warm water in your cold water lines. But if that is what people are doing I'm going to put in a T into my copper lines tonight and be done with it. I can sweat a pipe no problem and was thinking of replacing a dripping valve anyway. Maybe I'll just cut it all out and redo it tonight. Would make life much simpler.

sfsuphysics
10/25/2016, 12:29 PM
Forget examples of heating your tank, look for those who use boilers for radiant floor heating, it's the same principle but with less heating necessary for our tanks people often tie into the water heater.

If you tee into the hot pipe, with a pump you can force water through your loop of pex or whatever you use, then the other side of that tees right back into the cold input for your water heater, as soon as water leaves the water heater it needs to be replenished, where is that going to come from? It's going to come from the water you're displacing in the heating line as the pump will push it through. The water will not circulate through the rest of the cold water lines of the house for the simple fact that if faucets aren't open water can't go that way, now it is possible if the heater is running and you're taking a shower it can go the cold way but a lot of that depends upon how close your open faucet is plus remember 40PSI (or whatever your street pressure is) will fight it.

That is an example of an open loop system, if you're really worried about the exchange do a closed loop system which involves a heat exchanger, and water from the water heater never goes to the tank it simply exchanges heat via the exchanger and the water in the tank's coil is always the same, you could also use a fluid other than water if you really want. It's a bit more safe/sanitary but it is a bit more expensive and complicated to setup.

Only reason I can think people attached to the drain valve was to tie it to the system in case there was a pressure issue... but I can't really wrap my mind around why you would do that even.

fishguy306
10/25/2016, 12:43 PM
Thanks for the information! That does make a lot of sense to me actually. I think that is what I'll do. Might as well replace do it the right way and get the leaking valve out of the way all at once. It'll cost me a few bucks extra but it'll be done correctly and a lot less likely to leak.

I've also looked into the open vs closed loop thing. I know the open is a bit more risky, however I plan on setting it to run once a day for 30 seconds regardless of temp to cycle it. Being in my basement I dont think I'll need it but rather safe than sorry. Thanks again for the info!

fishguy306
10/26/2016, 11:14 AM
Sorry for the double post, but just a couple more questions on this. I got the return plumbed in last night, solved all my leaks and everything. I have not put a solenoid on it yet, after my discovery this morning I think it is necessary. I ran the system last night. Tank and sumps were at about 69* when I opened the valves and turned them on, I let it run for a good 30-40 mins, it only got up to about 71.5* in that time. Now my house is cold at the moment, roughly 66*, and the hot water heater probably wasn't full completely while I was working, but I expected it to heat a bit quicker. In any case I turned off the pump and went to bed.

This mornings shower was only luke warm, I figured out the water was still cycling through the pex slowly, tank temp rose about another degree overnight. So I guess my concerns are that one, I feel like the HWH should be able to keep up with that slow cycle and not cause a lack of hot water? And two, everything I've seen implies this sort of system heats the water very rapidly.

I will say, my HWH is over 10 years old at this point. Without this loop it heats the water well still, too hot to stand if you go full hot, but I'm wondering if it just doesn't have what it takes to heat the water enough.

anbosu
10/27/2016, 03:11 PM
You may need to turn the temperature up on your water heater since you're going to be using it more now.

fishguy306
10/27/2016, 03:19 PM
It is fully turned up already actually. I've ordered a solenoid, I'm going to put it in and set it so it wont run an hour or so before people start getting up in the mornings, give it some time to heat back up