R/O unit going slow

[boyohboy]

Not sure what section of the forum this thread should go, but anway...

I have a used R/O unit (4 stages) that I've been using for awhile. Just suddenly it's going really slow.... I let it on overnite and only got 1 bucket (~5G) of R/O water.... normally (even the last time I useda few days ago) it can do 1 bucket in about an hour.

How can I tell if the filter parts need replacing? Is such sudden drop in flow indicative or anything need replacing?

 

[scott]

when my unit slowed quickly like that it ended of being the carbon "prefilter" that was clogged. the DPW in my town flushed the water pipes and it stirred up the sediment that caused my unit to almost stop completely overnight. i'm not sure if you can tell just by looking if a membrane needs replacement(other than dionizer cartridge) i keep a record of how much water has been filtered and periodically take some pure r/o water to the lfs that has a tds meter to make sure the membrane is still functioning properly. maybe you could try running water through each section separately to see which one is clogged. that's how i figured out my carbon block was clogged. hope this helps, it's just my personal experience with my own unit. good luck! -scott

 

[fishgeek]

water pressure , they wont really work below 25-30 psi
any fluctuations in your tap pressure

andrew

 

[boyohboy]

Don't think water pressure is a problem, there's just as much water coming from the tap.

Also I should mention, the "waste" water output from the R/O seems to be ok, pretty good flow like normal. But it's just the R/O water output that slowed down to drop-by-drop almost.

Not sure how to test each filter separately... it's a home-made unit someone else made..... have to figure it out I guess

Oh, and I have a TDS meter and the output water still read 0 TDS... just very slow.

 

[tjudy]

If you have not replaced the prefilters in a while you can try replacing them and see what happens. Can't hurt. Do you have a back-flush valve on the membrane chamber? If not, you should invest the $15 - $25 bucks to get one. I back flush my membrane chamber for one minute every 100 gallons of RO water. My membrane is going on 3 years of 100 - 200 gallons a week use without a drop in efficiency.

If the water is very cold you will lose some efficiency as well. Your tap pressure may have chnaged, regardless of whether the tap flows teh same as before. Do you have a pressure meter on the unit? That would be another goo investment. If pressure is below 50 psi, I suggest that you look into a booster pump. They really help with efficiency.

 

[boyohboy]

Woot, finally found out that's wrong!!

It's sorta related to water pressure.
But it's actually the rubber O-ring inside the faucet adpator that is getting a lil loose and moved out of its position and so actual water flow into the R/O filter unit is not much. Hence the drop in output.

man... that lil O-ring caused me so much headache

Forgot to say, thanksk all for the suggestions