Getting fed up with my RO

[Bent]

So, back last June I bought new carbon blocks, new sediment filters, new membrane, new check valve, new RO housing, and a second DI stage.

At first, everything was awesome. I was pulling about 97-98% rejection rates and life was good. (About 4-8tds)

Now for some reason my RO output is in the 40s and 50s. I have a booster pump so the pressure to the RO membrane is around 85 or so.

Is my membrane already shot after 10 months? What would cause this to happen?

 

[slief]

Sounds like the membrane is shot. Does your water municipality use chloramines and if so, are you using chloramine filters? How much water do you make at a time? If you are making very small amounts (less than 30 gallons), you will burn through cartridges quicker. The smaller the batches, the faster you will burn through them. Co2 in the water is another thing that will kill membranes.

 

[Bent]

Sounds like the membrane is shot. Does your water municipality use chloramines and if so, are you using chloramine filters? How much water do you make at a time? If you are making very small amounts (less than 30 gallons), you will burn through cartridges quicker. The smaller the batches, the faster you will burn through them. Co2 in the water is another thing that will kill membranes.

Yeah I'm not making water like I should be. I need to get a double float switch and put one toward the bottom of the barrel instead of the single switch at the top.

Ordering another membrane now.

 

[Opus123]

Small batches shouldn't really matter too much. I do mine in 5 gallon increments and always have and my RO membranes last 4 to 5 years. What is your setup? What micron size is your carbon block? Chlormines could be the issue expecially since you are running a booster pump so the water isn't in contact with the carbon as long as normal.

 

[tkeracer619]

I'd get a 99% rejection spectrapure membrane and drop the booster pump pressure to 80.

I'd also address the chloramine question before bringing it back online.

 

[slief]

Small batches shouldn't really matter too much. I do mine in 5 gallon increments and always have and my RO membranes last 4 to 5 years. What is your setup? What micron size is your carbon block? Chlormines could be the issue expecially since you are running a booster pump so the water isn't in contact with the carbon as long as normal.

It does make a big difference. Particularly with the DI cartridges since the first few minutes of operation are putting higher TDS water into the DI's. Also flushing can make a difference in longevity. My unit has an auto flush. That said, I suspect it something in the tap water that's causing it.

 

[Opus123]

You are correct about the DI but not about the RO membrane. Also flushing the RO membrane does nothing to help the longevity of the RO membrane, at least not on our small consumer units. Now if you are using the term flushing meaning to by pass the DI for the few first minutes after startup, that will make the DI last much longer.

 

[slief]

You are correct about the DI but not about the RO membrane. Also flushing the RO membrane does nothing to help the longevity of the RO membrane, at least not on our small consumer units. Now if you are using the term flushing meaning to by pass the DI for the few first minutes after startup, that will make the DI last much longer.

I was talking about back flushing to improve DI longevity. My unit pulls RODI water from my holding tank and uses it to backflush the the system. It performs a flush every 30 or so gallons. Agree it won't do anything for the RO membrane but it does help the longevity of the DI cartridges.

 

[Opus123]

Sorry Bent, we got a little off track. Let us know your setup, ie how many prefilters, what kind and what micron size. Also give us your current TDS numbers at the tap, after RO membrane and after DI. The brand and gpd of your membrane would also be helpful. Also, is this city or well water?

 

[Marcio T.D.]

Membrane can be damage by bacterial film if you not flushs at least once a day, bacterial will make micro holes at the membrane shortening longevity