Bad DI resin = higher TDS?

[Saltyreef]

That seems to be a common misunderstanding what a "flush" valve does.

I mean in theory it sounds good. Blast the dirty side of the membrane to keep the filtering membrane clear....if only it did anything to lengthen the life of a membrane...lol.

The real resin destroyer lies in the clean water effluent

 

[bevo5]

not if the dual membranes are in series... could be 1:1. but OP didn't say... at any rate OP replaced filters and DI and its fixed

My waste water is pretty low. I close the valve to get pressure up above 100 and TDS stays at zero, so I figure it's ok if there isn't much waste water. Is that accurate?

 

[Biglew11]

My waste water is pretty low. I close the valve to get pressure up above 100 and TDS stays at zero, so I figure it's ok if there isn't much waste water. Is that accurate?

if you're just closing the flush valve and still have some waste water coming out then yes this is right. if you are completely stopping the waste water then it is wrong