Check Valve Sizing?
Sorry for the long post but wanted to make sure I gave all pertinent details...
I've just moved my whole house RO system to another location. The RO system is working great & dumping the good water into my 300 gal atmospheric storage tank. But in the process I cut out & tossed a pipe section at that tank that I now think had a check valve in it. When I fired the pump up it worked fine until it shut off & then water rushed back into the tank.
My pump is a 1/2 hp StaRite PNC1 shallow well jet pump to pump out of the storage tank & pressurize a captive air tank that feeds the house. The water level in tank is 6' when full. The pump sits 4' off ground level.
I've got a 1" PVC suction pipe on the pump. To get the system back up & running, I placed a brass 1" check valve next to the tank and it seems to be working. This may or may not be a temporary fix.
I question whether a 1" check valve is the right size for a 1" line. It seems like the check valve itself, even when open, constricts the 1" down considerably thus limiting the amount of water moving thru the pipe & to the pump. I'm wondering if I should install a 1 1/4" or bigger check valve so that the 1" line is able to stay full of water. I think the piece I threw out had a larger check valve than the piping...although when I threw it out I was unaware there was a valve in it...oops!
Can anyone tell me what size valve I should have in there given my setup?
Also, should it be a brass or plastic valve?
And lastly, should I use a foot valve or check valve? Someone told me to use a foot valve but I fail to see the need given the fact that the water in the tank is clean...what we drink...so shouldn't be anything that needs to be filtered out.
Thanks for the help...I really appreciate any help I can get!
Use the same size check valve as the line that it's on.
Doesn't matter whether it's a brass or a PVC check. That has to do with cost and your personal preference. IMHO, the innards will last about the same.
The pump inlet should be closer to the bottom of the tank, otherwise you leave a lot of stagant water in the tank and that is not good when using an atmospheric storage tank.
No metals of any kind with RO water; it eats them up adding them to the water. That includes the pump unless it is SS adn even then I suggest plastic. Lead free brass still has 2% by weight of lead in it....
Your check valve should be on the inlet end of the pipe and should be plastic. Brady makes many sizes of plastic check valves. The 1" check is the rght size; the same as the pipe ID as Mike says.
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