RO back flush

[bc_slc]

I have had a 5 stage RO unit for about 2 years. Since upgrading my tank, it seems like I burn through filters (carbon/sediment) faster now than I used to. They work fine as my TDS output is 0-1, but the outflow of water slows down to almost 4gal/day. Once I replace the filters, things pick right back up.

1. Would an aftermarket "flush valve" kits help with this?
2. Do I need to replace all 3 of the prefilters (1 sed, 2 carbon)?

Mat

 

[dwdenny]

I always change out my filters at the same time just to keep from confusing myself when did I change and what did I change I write it down just forget where I out that paper A flush valve might help but not sure. How much of an upgrade did you do gallon wise and how much more demand are you putting on the RO unit?

 

[bc_slc]

My tank went from 55 gal to 170. When the RO unit is running fine, it makes more than enough water. I probably only draw 3-4 gal a day or so from it. A few gallons for top off and the rest I store up for water changes.

Anyone else?

 

[steve-s]

You'd actually be suprised what a flush valve will do to extend filter life. Moreso prefilters but considering the cost of the valve, a cheap investment. I remember a friend I helped install his unit initially I told him to run the flush valve open 15 min every month or so and whenever the water main was shut off or there was heavy rain fall. He didn't and when I went over one day I turned it on to show him why. The amount of dark silty water from the waste line was nasty. The unit was installed a year ago August and still has a TDS of 0. Keep in mind though that my area has a tap TDS of 11.

Cheers
Steve

 

[bc_slc]

thanks for the heads up Steve.

Does the flush valve do anything for the prefilters or just the membrane?

 

[mattseattle]

I don't see how it could do anything for the prefilters as it's mounted after them and right before the membrane. everything i've read says it is just for flushing the RO membrane.

My unit has one built in and I use it every week. I also change out my prefilters every 6 months.

 

[reedman]

I'm in the same boat as matt. Mine flush kit only flushes the RO membrane...nothing else. It does extend the life of the membrane though.

 

[mattseattle]

I think a booster pump would probably help you out more than a flush kit with the issue you described. A flush kit would not hurt either.

I bought a booster pump right before the water got so cold and it's been amazing. Production has not dropped off at all even with the incoming water temp. so cold.

 

[steve-s]

Does the flush valve do anything for the prefilters or just the membrane?

My bad, you are right. It helps with the RO not the prefilters.

Cheers
Steve

 

[bc_slc]

what booster pump are you running matt/reed?

 

[mattseattle]

I'm using the Aquatec 8800 RO Booster Pump

It works especially well when the water is as cold as it is right now. I can make a gallon of RO water in about 10 minutes.

 

[bc_slc]

what is the rating on your RO filter membrane - how many GPD without the booster? and is it bad to overdrive the membrane? 1gal/10min = 6gal/hr = 144gpd.

 

[mattseattle]

I have a 100 gpd membrane. It's probably more like 15 minutes to a gallon. I'll have to time it next time I make water.

Not sure if it's bad to overdrive a membrane or not... the booster pump really can't over drive it, I would think. it only bumps the pressure up to about 70 psi, I think.

 

[reedman]

I run the same booster pump as Matt. Works great and has increased my output water/decreased my waste dramatically. I think my pressure is between 70 & 80 psi (upper end of safe I think).