3 replies to this topic

[cravindran]

We have a DM water unit with cation and anion units. The pH of DM water used to maintain at 6.5 but suddenly it dropped and maintaining at 4.5 for the last few days though the conductivity and other parameters like conductivity , hardness and chlorides are within limits

The resin in both the columns are 3 years old

Please through some light on how to rectify the problem

C.Ravindran

[S.Chittibabu]

Confirm whether the low pH you are referring is at Anion Outlet or DM water storage.
If it is from Anion out let, Check for the (strong base) anion resin exchange capacity.
Check for Organic fouling.
If the pH is at Demin storage then go for Carbon di oxide trap which will be an attachment with your breather valve arrangement.

We have a DM water unit with cation and anion units. The pH of DM water used to maintain at 6.5 but suddenly it dropped and maintaining at 4.5 for the last few days though the conductivity and other parameters like conductivity , hardness and chlorides are within limits

The resin in both the columns are 3 years old

Please through some light on how to rectify the problem

C.Ravindran

[ponnusj]

We had faced a similar issue in our DM water some time ago. We had very low Na+ readings in the DM water then. We solved it by adding calculated amount of NaOH to the DM water to maintain the pH above neutral.

[Mehrdad]

Hi
Dissolving CO2 In Water Is One Reason For Decreasing Of PH.