Pure Water Permeability test

[RO_Guy]

Does anybody else do a PWP or "PEP" test on their ROs after a wash or a rinse?

I was doing it successfully last year but this year I can't seem to get the membrane pressure to 200 psi on my pressure gauge. I replaced the gauge thinking it was faulty but I'm getting the same results. Using filtrate I turn the concentrate valve all the way in as well as the membrane pressure valve closed with 1 turbine running and can't reach 200 psi.

I can use the RO to concentrate normally without any problems.

Any ideas?

[RO_Guy]

Nobody else does this test?

[gmcooper]

I don't do those tests but I can't get my new unit up to pressure yet. 145 max but the more gallons that run thru the ever so slowly the pressure climbs.