RE: DI Resin

[Randy1]

My DI add-on filter dosen't fill with water all the way. Today I noticed the resin changing color at the bottom, it this normal?

[Thefilterguys]

It is running normal as it is low pressure the cartridge inside is running full to overflow. Your RO water is in full contact with the resin and should be producing zero TDS water.

The color change is exhaustion by TDS absorbtion. Once you start to get a reading of 2-3 in your product water and your resin has turned amber it is time to change resin. You may have elevated CO2 levels in your municipal water.

Jim

[Randy1]

Thanks. Will all of the resin turn color or only partial? Yes, its producing 0 TDS.

[Thefilterguys]

Generally they turn all amber but I have seen some both black and amber That's why a TDS meter is handy the reading is the key. The color change is just a visual heads up.

Jim