Decreased performance (by almost 50% at times) with 2nd pass through RO

[milligkl]

Hello everyone,

I have a Deer Run 500 unit, and I get anywhere from 350-460 gph on my first pass through the RO. On my second pass I get anywhere from 180-300 gph. I have shut the RO down and done the backwash and rinse when it has been running for more than 4 hours and while it improves the performance slightly it still seems to really struggle with the more concentrated sap. I expected some decrease in performance but is there anything else that I can do to help have it running better? Anyone else out there with a Deer Run RO have similar issues?


Thanks,
Kevin

[maple flats]

Yes, the drop is because of the pressure a Deer Run operates at. However, I get 240-260 GPH on first pass, I then do a recirculate to concentrate and get less but I'm not sure how much less. My RO is a 250.
If you only get350-460 call Ray to trouble shoot. The 240-260 is with sap at 37-38 F. colder lowers it some. What micron rating pre-filters are you using?

[maple flats]

By the way, an RO that runs at higher pressures does much better, but the up front cost is far higher.