Auto top off: resevoir w/pump vs solenoid on RO/DI

[daveverdo]

I am installing a basement sump and can run pipe to a RO/DI unit close the sump.

What are the pros and cons of either type of topoff?

The way I see it is the resevoir system needs to be manually refilled whereas the direct RO/DI does not.

Dave

[MeuserReef]

Solenoid on RO/DI is the way to go. I have used this method for over a year now and would never do anything else. Its just so darn convenient not ever having to worry about topping off.

The key word for this style of ATO is "REDUNDANCY"

- Multiple float switches
- Timers
- redundant solenoids on input of RO unit

[RicGio]

I agree with MeuserReef! Solenoid controlled by a timer tied to a float switch. Redundancy is KEY. Do you work in a data center Meuser?

[tonga_man]

As stated - Redundancy...
I use RO/DI with a solenoid into a JBJ ATO that is plumbed into my sump through a Kent float. The ATO uses two floats (high and low) with a timer, and if that some how continues to run (doesn't time out) the float will mechanically stop the flow also.

[daveverdo]

I was planning on high and low float switches and a single solenoid before the RO/DI.

I may be missing something but what is the function of the timer and which timer do you use.

Dave

[tonga_man]

The timer is built into the JBJ ATO, the solenoid will only stay energized for so long before it times out. I know that it normally takes about two min. for my sup to fill once the low switch is triggered (I have my floats very close together) so I set my timer to about four min. Even if the high switch never triggers the timer will still shut off the water flow. Then if that malfunctions the Kent float should stop the flow.

[Chrisrush]

This is very similar to what I will be doing but I will be using the reefwerks holding tank controller instead of the JBJ unit. Comes complete with 2 float switches and a solenoid. My timer will be on my profilux controller. My wife and I each flooded the ato container in the past and I don't want that to happen again.

[MeuserReef]

<a href=showthread.php?s=&postid=11334454#post11334454 target=_blank>Originally posted</a> by RicGio
Do you work in a data center Meuser?

No. Actually I work at a food distribution warehouse where I manage the facility infrastructure, including IS/IT systems. I deal ALOT with redundant systems. Everything from the R404 Deep Freeze Refigeration units that keep our freezer @ -5 degrees to the VMWare Virtual Server Hosts that run our File/Print/Backup servers all have redundancy built in. It really helps one sleep at night :D

Here is a crude sketch of how my system is setup.
http://img.photobucket.com/albums/v708/Original_Tarheel/ROAutoTopOffSchematic.jpg

The timer is your protection should the float switch(es) fail.

[Saboral]

I simply have my RO unit tied to a automatic horse water bucket float valve I picked up at tractor supply. Using the auto-shut valve I got from Coralife to cut of the water supply when the float closes. Its been in use for two months and not a single problem and it only cost me $20 and has no metal or electronic parts, I'm happy with it.

[Pbrown3701]

I use the float and solenoid but fill my reservoir. I then use a peristaltic pump to pull water from the reservoir and push it through a Kalk reactor on the way to the sump.

[MeuserReef]

<a href=showthread.php?s=&postid=11336000#post11336000 target=_blank>Originally posted</a> by Pbrown3701
I use the float and solenoid but fill my reservoir. I then use a peristaltic pump to pull water from the reservoir and push it through a Kalk reactor on the way to the sump.

I just installed my DIY Kalk reactor in-line between the RO unit and the sump.

Its been working quite well for me in this configuration. I was forced to engineer around not having room for a fresh water holding reservoir, but looking back, I think I would have done this regardless (and will on future setups)


**Note**

I still plan on putting a Coralife manual float valve on the supply line in my sump. Since my RO has an Auto Shut-Off valve, I would be protected in the event that both solenoids became stuck in the open position.

[Saboral]

<a href=showthread.php?s=&postid=11342188#post11342188 target=_blank>Originally posted</a> by MeuserReef


I still plan on putting a Coralife manual float valve on the supply line in my sump. Since my RO has an Auto Shut-Off valve, I would be protected in the event that both solenoids became stuck in the open position.

I don't recommend the coralife valve. I bought one and it would never seal and contained no rubber or anything that remotely resembled a seal. I really would recommend getting a high quality float valve from somewhere like tractor supply. Like the one I use:

Float Valve (http://www.tractorsupply.com/webapp/wcs/stores/servlet/ProductDisplay_10551_10001_28397_______14602|14606|14614|28397?listingPage=true)

[MeuserReef]

Thanks Saboral. The unit that I have has a rubber stopper that presses pertty tightly into the hole where the water comes out of it. I have never actually used it so it could be a piece of crap like the one you used.

In looking at the valve in the link you provided, does the valve have a cover (black part in picture) over the actual valve (red in picture)? I hope so because the metal on the balck plastic part would not be good in a saltwater environment.

[daveverdo]

What solenoid do you guys use?

Where did you get them?

Same questions on the float switches.

Dave

[MeuserReef]

Solenoid = McMaster.com

I use the 120V model, but the 12V model is also popular. Make sure to get the "Normally Closed" (NO) type. They will only allow water to pass when the cvalve has power (which is controlled by your ATO)

Float switches = aquahub.com

Get 2 (or 3) and run them in series.

[Donw]

If the return area in your sump is small and your rodi incomming tds is fairly high then I would stay away from the solenoid type ato unless you add a pass to waste system.

Don

[protege]

I use straight mechanical topoff float, no pumps/valves/etc.... The exact same that is on my RO/DI storage unit. Unfortunately, I cannot get a picture of my sump due to the massive cluster I currently have under there, but it is the same as the picture on my RO/DI storage.
I cut a hole in the sump, and added the float. There is a 5 gal water jug that is elevated slightly higher than the sump and 1/4" tubing going into the float. When the float drops, it opens and allows water to flow into my sump. This has worked very well for me. I just add RO/DI weekly to the 5 gal. container to keep it topped off and everything is fine. I choose 5 gal, that way if the float failed, I wouldn't fill up my entire house.. :)

Oh, got the float from airwaterice.com

Float in my RO/DI (Same as in my sump)

<a href="http://s248.photobucket.com/albums/gg169/protege473/?action=view&current=PICT0048.jpg" target="_blank"><img src="http://i248.photobucket.com/albums/gg169/protege473/PICT0048.jpg" border="0" alt="Photobucket"></a>

[rbursek]

One problem with the ATO is very short runs on your RO/DI. So it does not have a chance to get rid of TDS creep, and short runs shorten the life of the membrane.
Bob

[kcress]

MeuserReef; The two solenoids seem to be a problem. What happens when one fails open? You will not have a clue... Until the second one sticks open.

In most cases you would use a controller that turns one off and checks for no flow then turns the opposite one off and checks for flow. If both stop the flow then turn both off with assurance.

[kuhli]

Any reason why you're placing the solenoids in front of the RO unit? I've a tank on my house one and it wouldn't make sense to implement it that way...

[daveverdo]

If it is after the RO unit there is always pressure on the unit. Before the RO then there is not pressure when the water is off.

Dave

[Donw]

<a href=showthread.php?s=&postid=11842178#post11842178 target=_blank>Originally posted</a> by daveverdo
If it is after the RO unit there is always pressure on the unit. Before the RO then there is not pressure when the water is off.

Dave

Yes and thats where its supposed to be. Before causes low pressure starts.

Don

[MeuserReef]

<a href=showthread.php?s=&postid=11842340#post11842340 target=_blank>Originally posted</a> by Donw
Yes and thats where its supposed to be. Before causes low pressure starts.

Don

Don,

I have been using mine before the RO for about 2 years and have 0 TDS to this day. What exactly will the "low pressure start" do to the RO unit that will hurt it? Im assuming that the only pressure-sensitive part is the membrane, correct?

[Donw]

<a href=showthread.php?s=&postid=11842493#post11842493 target=_blank>Originally posted</a> by MeuserReef
Don,

I have been using mine before the RO for about 2 years and have 0 TDS to this day. What exactly will the "low pressure start" do to the RO unit that will hurt it? Im assuming that the only pressure-sensitive part is the membrane, correct?

0 tds is a meaning less number since the DI is capable of removing so much. Membranes need to be started under high pressure to help cut down on scaling and tds creep that is consuming your di resin and shortening the membrane life. One reason better rodi units run higher percentage asov valves rather than the standard cheap 60% valves.

Don

[kuhli]

I can't see any reason to keep the pressure off of an RO unit so putting the solenoid after the RO unit makes the most sense to me.

[MeuserReef]

Don,

I had originally set my ATO up with the solenoid valves before the RO/DI because of the fear that the metal inside of the valves would be in direct contact the water going into my sump.

I have since learned (manily by your posts) that there is no "contamination" danger involved with running the solenoids after the RO/DI.

[jtma508]

I'm just starting my own set-up and had arrived at the same design as the schematic on page 1 of the thread. However, becasue we have well water I need to use a booster pump for the RODI unit. Could I just substitute the pump for the second solenoid?

[Donw]

<a href=showthread.php?s=&postid=11845859#post11845859 target=_blank>Originally posted</a> by jtma508
I'm just starting my own set-up and had arrived at the same design as the schematic on page 1 of the thread. However, becasue we have well water I need to use a booster pump for the RODI unit. Could I just substitute the pump for the second solenoid?

A booster pump uses a pressure switch to turn on and off. Put the solenoid on the ro output so that the booster pump pressure switch see's the pressure on the rodi system not just the pressure between the pump and valve.

Don