It's time... DIY auto top off questions

[jaded]

does anyone know how much pressure I need to stop with a solenoid before the RO/DI? I dont even know where I would start looking for that information.

[matt]

I was thinking about a dual float switch (no timer) The main float switch would open the solenoid when the water dropped and the backup float switch would always be "open" unless the water reached high enough to close the solenoid. In other words the backup would be an open circuit all the time unless the main switch failed... if that happened the rise in water level would close the solenoid. If they both fail I would have a mess...

Is there a problem with using this solenoid valve It has a brass fitting. I'm not sure what that would effect if anything

You're going to have the issue of your filter turning on-off-on-off constantly with the set up you described. I've heard of using a 2 float switch arrangement in which both have to be either on or off for the solenoid to fire. The switches are set at slightly different depths. This way, the level drops to open the first (higher) switch, nothing happens, it keeps dropping and opens the second switch, water comes on, starts rising, closes the second switch, stays on because both switches need to close, rises to close the first switch, then the water stays off until it drops below the second (lower) switch. I think some older thermostats used this type of principle to keep the AC/heat from constantly going on-off as the temp fluctuated slightly.

Don't know about the solenoid, just obviously anything with brass in it should go before the filter. I got mine from Mcmaster-Carr, but I have no idea what the number is. It's all on that monstro thread on reefcentral from a couple of years back "DIY auto top off with solenoid". As far as pre-filter pressure goes, you're looking at residencial line pressure, which I believe never exceeds 75 psi; probably quite a bit lower, and I'm sure any plumber could tell you.

Good luck!

[jaded]

I would have no problem using a timer and solenoid if thats a better/safer way to do it... please explain further

P.S. Thanks for the help so far!!!

[OldSalty]

Dont run the line in the attic unless you want HOT water in your tank in summer and cold in winter. plus in winter your line could freeze. My ro unit is connected to a fluidmaster toilet valve in a 5 gal bucket and gravity feed to a kent float valve in the sump. Less than 10 bucks to build. Has NEVER failed in the 5 years its been in operation. no pumps, soleniods or electricity. Why make a simple system so complicated with all this other stuff?? PM me and I can show you the SIMPLE way.

[jaded]

I dont have any room under the tank. The tank is on a wall in my living room... If my wife sees something like your explaining then I'm going to be in serious trouble.

I'm not sure what my best option is. I'd like to have a simple system but I cant figure a way to do it without making it complicated and running lines in the attic. I'm thinking that the temperature of the small amount of water in the lines wouldnt effect the 160+ gallons in the tank and sump, but I really dont know.

Wow I need advise!!! The closest place to store any quantity of water is in a closet of my guest bathroom, which is going to be pretty far away (Im geussing 40-50'). Of course I could put the RO/DI and water storage on my back porch but that would be bad news in the summer and winter.

[NaCl_H2O]

Ok, here is what I am working on ...

RO/DI has a pressure type auto shutoff solenoid (non-electric). If the RO/DI water output is restricted (float valve, ball valve, whatever) presure builds up on the output side of the RO/DI and shuts off the input side. However, I think these pressure type shutoff solenoids are only good for 90gpd and less?

My RO/DI output goes to multiple sources (e.g. water change barrels), but all but the topoff are usually closed off with a simple ball valve.

I have a Reef Fanatic Level controller which switches on a 110v plug when the water is low.

I will be conecting an electric solenoid (normally closed) to the output side of the RO/DI with the solenoid plugged into the topoff controller.

When the controller senses that water is needed for topoff, the elecric solenoid will open releasing pressure on the RO/DI output side, which will release the pressure solenoid and input to the RO/DI will open. When the water level is back to normal, the controller will close the electric solenoid, causing pressure in the RO/DI output line and thus shutting off the input side to the RO/DI.

Now, a little more complexity. The output from the RO/DI will feed the input side of a sealed Kalk Reactor. Water flow into the Kalk reactor will force water through and out the reactor to top off the tank. With a DPDT relay, Kalk mixing will be turned on, via a small powerhead on the kalk reactor, whenever the electric solenoid is off/closed.

I am going to have Pete build the Kalk Reactor big enough for my system.

Make sense???

You are welcome to come se it once I get it all working.

[jaded]

Yeah that sounds very nice!!! I'd love to see it. So you actually have a solenoid on both in and out of the RO/DI...I like it!!!

[NaCl_H2O]

So you actually have a solenoid on both in and out of the RO/DI...I like it!!!

Well, yes, kinda ... the solenoid on the "input" side is the autoshutoff solenoid by Kent (and others). Not really on the "input" side, but it does shutoff the flow into the RO/DI - kinda hard to explain without showing you in person.

[jaded]

I'd love to come see it when its up and running... Hey I'd love to come and she that magnificent setup even without the auto topoff to look at!