Help me with my RO unit!!

[jherrin215]

I just replaced the filters on my RO/DI unit with new filters from BRS about 2 weeks ago. I also just recieved my TDS meter today. I checked my TDS at my kitchen sink and was reading 147. I checked it coming straight out of the RO/DI unit and am still getting 5 TDS. I also replaced my DI resin with the color change kind from BRS and after only 2 weeks it has already turned from Blue to Brown. I am leaning towards needing a new RO membrane but wanted to double check to see what everyone thought before buying one or if my 4 stage just wasn't enough for my water. Thanks in advance for the advice!

 

[bigdoug]

are you getting the proper pressure going into the unit, i believe that if you have low pressure the unit will not function properly. I have the same unit and i get about 600gal out of the color changing DI resin. My tds going in is around 138 and out 0.

also it sounds like you have a handheld tds meter, does it possibly need calibrating?

 

[bmkj02]

How old is the membrane? Sounds like it may be going bad

 

[jherrin215]

The meter says it's factory calibrated and that it can't be calibrated. Pressure may very well be my issue. I have good pressure in come places in the house while it is terrible in others. My kitchen sink for example is pathetic. The membrane is probably 1.5 to 2 years old

 

[dwl]

Check the RO water, before the DI unit and see what it yields.
That will tell you what the membrane is doing.

 

[jherrin215]

Thanks dwl, tried checking the water right after the RO but before the DI. I still had 91TDS! I would assume this is way too high and that my RO membrane is bad, which is just working my DI to death. I am going to order a replacement today for the RO and the DI and be done with it for a while hopefully.

 

[reeferhabit]

I am having a similar issue, except my TDS reading is 40. Still way too high.
I noticed you mentioned your membrane is older which is probably the source of your issue. However, mine is only 2 months old. My tap water reads 144, so I getting some purification, but I can not figure out why my TDS is not 0-5.

 

[jherrin215]

Yeah, that is way high. Mine was only 5 after the DI, I just waw that it used it WAY too fast and after checking still had 90 before the DI, I know why it's so high now!!

 

[chimmike]

If you didn't replace the RO membrane with all the other filters you're just wasting your time and energy.

 

[chuckreef]

after the RO but before the DI. I still had 91TDS!

Yes, any value above 10 out of the RO memebrane indicates time for a new membrane, or it is not seated/sealed porperly in its housing. Usually it will be 2 to 7 range depending on the source water and the specific RO memebrane.

Anything above 1 out of the DI resin is too high. Preferabbly, it will be zero and you will change the resin as soon as the effluent begins to read 1.

 

[jherrin215]

If you didn't replace the RO membrane with all the other filters you're just wasting your time and energy.

You always change your membrane when you change you filters?? This contradicts everything that I've read. Everything else I've read says that changing your other filters is what extends the life of your membrane and that it doesn't need to be replaced near as often.

 

[chimmike]

I have no idea the stability of the quality of my tap water, so I find it safer for me to just replace the whole shebang rather than risking it.

 

[dwl]

I would certainly not be replacing my membrane with every filter change.
The pre filters are supposed to be there to ensure the membrane can have a long life, usually in the 2 - 5 year range. The pre filters should be replaced every 6 months.

The pressure gauge if present is to give an indication of the filter's remaining life and the TDS meters are to be used to indicate when to replace the membrane and/or DI resin.

Good luck.

 

[jherrin215]

yeah that would be my suggestion, order a 10 dollar TDS meter to check before you replace a 50 dollar membrane uselessly, over and over.