RI/DI problem

[mike31154]

Originally Posted by Coleus

so here is what i found out

water into RO is 172, out of RO is 20 and out of DI is 4

So which one is broken?

Thx

What type of RO membranes are you running? Most 75 gpd membranes will provide a rejection rate of at least 98%. If I've done the math correctly using your numbers I get a rejection rate of 88% and you're using two membranes. My single 75 gpd membrane takes the input TDS of 210 down to 1! I'd recommend having a look at your RO membranes. If their rating is more than 75 gpd, then the rejection rate will be lower, but with two membranes you probably should do better than 88% before the DI. You mentioned in an earlier post that you replaced the restrictor? Quite often the last component changed or disturbed in any system will be a good place to start looking for problems or errors.