Low production from pure clean spot free

[CLSkover]

I am currently producing only 2 GPM of spot free water. I have changed the membranes, cleaned the stabilizer, and changed the pre-filter. Pure Clean says the production drops when water temps drop. The problem is that the production keeps dropping. I have done all the 5 gallon bucket tests. Anyone have any ideas on something that I might be missing??? Thanks in advance.

Chris

 

[jfmoran]

Temp

Check the manual, pretty sure I recall a warning in there that incoming water temperature below 77 degrees F will significantly impact the production and output of your RO system. You may need to "pre-heat" the water in the colder months prior to sending it through your RO system to maintain your max output.

John Moran

 

[MEP001]

What pressure is the system running?

 

[Greg Pack]

What is the expected output of this system? You say "membranes" so I assume a two membrane system.

As mentioned temps affects performance significantly. A standard filmtec 4x40 membrane is rated for 3.33 gpm at 77 degrees but accoring to dow temp tables will only put out about 1.95 gpm at 50.0 F water. Many in cold climates use a blending valve to enhance performance of the system.

temp conversion table on page 168 of this .pdf

http://www.dow.com/PublishedLiterature/dh_0344/0901b80380344689.pdf?filepath=liquidseps/pdfs/noreg/609-00071.pdf&fromPage=GetDoc


Aside from temps- lower than normal output+normal operating pressure= flow restriction- usually caused by clogged membrane, but can be caused in some systems by a partially closed valve or kinked hose on the discharge side of the membranes.

I'm going to also assume you replaced membranes with the exact ones that were in there previously. Many membranes look alike, but are configured for different pressures.