Ro-di problem

[migas_01]

I`ve replaced my 100 GPD RO membrane today for a DOW FILMTEC 75 GPD RO membrane with matching flow restrictor. I also replaced the sediment filter, carbon filter and the DI cartrige had been changed about 5 days ago with Fauna Marin MB20 mixed bed resin.

Before changing the RO membrane and cartriges I was getting a TDS reading of 2ppm and now I get a reading of 5ppm ( 12ppm after ro membrane and 5 after DI ) TDS entering the RO unit is 175ppm.

Also when I flush the membrane TDS goes down to 3ppm and when I close the flush valve it goes back to 5ppm.

The unit has been working for over 2 hours so I think that new membrane fluid is not the issue.

Any thoughts about what might be wrong??

[Soymilk]

Looks like your membrane is working right

175 tds in
12 tds out (93% rejection rate)

Something is wrong with your di.

[migas_01]

I still don`t understand why I had better TDS readings with the old 100 GPD membrane. The DOW FILMTEC 75 GPD its supose to have a better rejection ratio than the 100GPD membrane min 96% and max 99% rejection.

[migas_01]

Thoughts anyone??

[migas_01]

My new 75 GPD membrane came with 350 flow restrictor is this a problem??

[sjm817]

AFAIK, a 75 GPD should have a 550 restrictor.

[migas_01]

AFAIK, a 75 GPD should have a 550 restrictor.Is this bad for the membrane or can it afect the membrane performance?