Off Season

[wnybassman]

So I noticed today that a fair amount of water was coming out of my small RO and saw it was coming out of the "plugs" I put on the intakes and outtakes. It was also maintaining about 20psi on the gauge. I am assuming it is because I last rinsed it and put preservatives in it when there was still snow on the ground, and now that it is hot the water expanded.

Should I crack it open and relieve this pressure, or keep it relatively air tight?

I still have permeate left and was also thinking about a rinse and a new batch of preservative for the rest of the summer. Good idea or not?

[Bricklayer]

Did you leave the membrane in the unit or store it in a seperate unit?
First year I left permeate in my RO and took membrane out. Closed all valves and left it. I found it was pretty slimey and gross the next season. So this year I took membrane out of unit and stored it in storage solution like normal but once membrane is out I mixed up a citric acid mixture and cleaned the RO out on low pressure and flushed it out. Then drained it and closed valves.
Letting membrane storage solution sit in your RO over the off season is probley not a good idea. Might not be good for the seals and such.

[Urban Sugarmaker]

I store my membrane in solution in a 4" PVC vessel I made with parts from Home Depot. I think you'll want to drain the main unit's parts and keep them dry for the rest of the off season.

[wnybassman]

I left the membrane in the RO as per the manufacturers instructions. Perhaps next year I will have a separate vessel.

[maple flats]

Either one is good to store the membranes, but be sure you have properly cleaned with Soap then Acid and completely rinsed and finally put in the preservative. Then you can store it in the RO or separate storage canisters. I've done it both ways, mine is in the RO this year. I just close the needle valves and let it set until next year. Next year I will also leave it in the RO but in 2020 I will again be sending it out to LaPierre for cleaning and testing, thus they will go in my separate canisters.
One consideration might be the heating issue, if in the RO it must not freeze, if in a separate canister that can be moved to a safe location where it will not freeze.

[wnybassman]

One consideration might be the heating issue, if in the RO it must not freeze, if in a separate canister that can be moved to a safe location where it will not freeze.

No worries about freezing. It's on a dolly and I have an insulated climate controlled root cellar in the basement of my barn that it gets rolled into when cold.

[maple flats]

OK then as soon as you finish pumping the preservative in, shut the pump off and close the needle valves and any recirculation valve to hold the liquid in full contact with the membrane. If the valves are left open the pressure vessel can leak down a little as air migrates into the canister and the top of the membrane can get dry. The same thing if stored in a storage canister (many make them out of PVC pipe), make sure it is full and store it upright. Check a few days after filling, air in the membrane works to the top and can leave the top dry. If you need to add water, do it, tighten the cap or plug and tilt the canister back and forth a few times to blend the preservative with the water you added. You only need to check and add one time unless you had to add a lot of water. In that case check again 3-5 days later.

[Urban Sugarmaker]

I left the membrane in the RO as per the manufacturers instructions. Perhaps next year I will have a separate vessel.

No harm in that if that is what's recommended.