RO recommended pressure??

[TCoach]

Hey fellow reefers,

I have my 7 stage 150 gpd RODI system running, and it is producing way faster than expected. it filled my 32 gallon brute in 2-3 hours vs the expected ~5-6. The waste line pressure gauge was reading 120 psi, and I think that is the issue.

What PSI is optimal for RODI systems? I thought I had heard 80, but I wanted to check.

Also, is the best way to lower the the pressure just to use a shutoff valve on the input line and limit the amount of water coming in?

Thanks!

 

[CK00020]

With the pump mine runs around 100 but 120 seems a bit high

 

[homer1475]

Measure the incoming pressure, not the waste water pressure. Measure before the pre filters, and right before the RO membrane.

The pressure going to the RO membrane should be between 60 and 90PSI. Any higher can damage the RO membrane.

I have the 150GPD system from BRS. My incoming pressure is 70, and I fill my 40G brute in about 5 hours as you had expected.

 

[Gtinnel]

The problem with having really high pressure is that you don't produce enough waste water. Without enough waste water everything that gets filtered out by the membrane doesn't properly get washed off of the membrane, which will reduce the life of the membrane. You can run with a higher pressure if you open a flush valve to "wash" the membrane off more frequently. Mine runs at 100 psi and so far I haven't had any issues, although mine is setup on a homemade controller to flush the membrane at the beginning and end of running, and once every 30 minutes.

As I understand it the pressure alone is not what is bad for the membrane.