first time running RO with new membrane

[Wanabe1972]

I am starting my RO for the first time and the membrane said to flush for twice the rated through put for 1 hour so roughly 200 gallons. When I do this do I use just the feed pump and run the concntrate needle valve wide open or tighten the needle valve down to run at working pressure? Thanks Jeff

[Clinkis]

Typically when you flush any RO you want the maximum flow rate across the membrane to flush out any contamination which means you want your needle valve wide open.

[Wanabe1972]

Ok so even with the needle valve wide open it will still put water through the permeate side? I'm going to wait till Fri cause its going to be 9 below Thursday night.

[wiam]

Ok so even with the needle valve wide open it will still put water through the permeate side? I'm going to wait till Fri cause its going to be 9 below Thursday night.

Yes there will be some. Your basically flushing the crud off surface of the high pressure side.

[bowhunter]

I have a new RO this year and have been experimenting with with the permeate flush. I have to flush for at least 30 minutes to get the recovery back and I get permeate even at 50 psi. I try to flush enough to get the performance back to the previous permeate flush.