RODI Issue - What am I missing?

[leewish]

Might be worth getting an inline tds, then you can also confirm when certain membranes are going bad.

I have 3 TDS meters on it. Just changed the batteries a few weeks ago. Going to check all the plumbing tonight.

 

[tharbin]

Might be worth getting an inline tds, then you can also confirm when certain membranes are going bad.

I have a TDS meter between my membranes and the DI stage to know when the membranes are shot. I think they are a good investment. With 170 TDS coming in your TDS to the DI stage should be less then around 8.5, depending on your membrane's rejection rate. A lot of 100 GPD membranes are 95% so 8.5 in the output line. 170 in is not too bad so your resin should be lasting for hundreds of gallons. I'd check your source water for Chloramines and test the TDS out of your membranes. If they are both okay you may have gotten bad resin.

 

[Largeangels]

When I said into RO/DI I meant #into RO, then #into DI. Then finally what is it out of DI.

 

[Uncle99]

When DI is used up faster than normal that’s an indication the membrane has either failed, or unseated.

 

[leewish]

Here is a link to my video. I also forgot to take a pic of the pressure gauge and showed my di resin.

 

[motoking_1990]

You may check with the municipal water company and find out if they changed what they are treating the water with. I watched a video couple days ago where one of the brs guys was warning about it in a 20 questions video.

 

[Naekuh]

I have a TDS meter between my membranes and the DI stage to know when the membranes are shot. I think they are a good investment. With 170 TDS coming in your TDS to the DI stage should be less then around 8.5, depending on your membrane's rejection rate. A lot of 100 GPD membranes are 95% so 8.5 in the output line. 170 in is not too bad so your resin should be lasting for hundreds of gallons. I'd check your source water for Chloramines and test the TDS out of your membranes. If they are both okay you may have gotten bad resin.

Agree'd as i was trying to have him give me what his TDS was POST RO, being fed to DI.
However its not just chloramines that can burn your DI, but also dissolved gasses like CO2.

If he said his TDS was great, and he swore by his resin source, i would probably have asked him to check the pH on his water, because if it is acidic, like pH 6 that will also burn though your DI.

 

[Reef.]

Agree'd as i was trying to have him give me what his TDS was POST RO, being fed to DI.

Yeah hard to say what is going on with only knowing the tds at the start of the process, knowing what it is at each stage would solve this issue much easier.

The most useful figure in this situation would be knowing the tds after the membrane before going into the resin…I would use a $10 tds pen for this rather than an inline, just unplug the tubing to draw off some water to test.

Also did the OP change the flow valves with the membranes?