RO/DI setups
First off, let me describe my RO/DI system then I'll pose a couple questions. Bear with me, I know this post is going to be lengthy.
I have a "The Filter Guys" OCEAN REEF MISER SIX STAGE RO/DI 100 GPD RO/DI system with an added booster pump.
Water comes into my booster pump, through the 3 pre-filters, then 2 RO membranes, then through a pressure switch which controls the booster pump, then into my 2 DI cartridges, and finally through the float valve in my Brute tub.
The Problem: With this system, my wastewater never stops running. Which is normally not that big a deal. I store roughly 25 or so gallons of water, so I only make water a couple times a month. That's when I go down, turn the water on to the system, turn the booster pump on, and wait for it all to fill up. Once the Brute can is full, the float valve closes, creates back pressure which turns off the pump. BUT... the waste water keeps flowing. So I have to remember to go down and shut everything off. Something which I have forgotten a few times until the next day. So I'm looking at finally fixing this system.
I have been under the assumption that it really isn't all that good for the pump to come on for a few minutes a few times a day. Although I'm beginning to wonder if that's not such a big deal. I mean, systems used solely for drinking water under sinks do that all the time. What I must admit, is I don't like the sound of that booster pump coming on in the middle of the night as it tops up my Brute.
It has been pointed out to me what I am missing in my system is an Automatic Shut Off Valve and a check valve in the permeate tube between the membrane and the shutoff valve.
After talking to a guy at Aquasafe is Sydney yesterday, I'm not sure if this will work either, unless I have a pressure storage tank. My understanding of this whole system being truly automatic is the check valve and ASV (auto shut off valve) rely on the back pressure created by a pressure tank. While the float valve in my Brute will create some pressure, as soon as a few millimetres of water is used by my ATO, the system would come on. While if I had a pressure tank, my understanding is I could use up several gallons of water before the system replenished itself. Depending, of course, on the size of the pressure tank.
So, I guess here's my questions:
1) Does any of this make sense or have I got fundamental flaws in my understanding of how these systems work?
2) If I DO have this all straight, why are we using 30 gallon Brute cans to store FW for ATO? My system, for example, probably uses up 3-5 gallons a day in evaporation. If I had even a 4 gallon pressure tank reservoir or even 2 in tandem (for a total of 8 gallons of FW), that would more than likely suffice for my day to day top off.
3) If all the above is correct so far, is it possible to allow a Tunze osmolator to operate a solenoid valve instead of a water pump that would open, allowing water to drain from the pressure tank into the sump when the infrared eye deems necessary?
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