PDA

View Full Version : Ro High TDS Help


BlueTang<3
11-13-2010, 08:03 PM
Well just changed my pre filter, carbon and di resin and the tds reading shot to 38 let is run for a few hrs and its still there. Does it usually go up this long. Or do i need a new ro membrane.. It was only at 5 ppm before i changed them but i noticed a but of cayno.

hillegom
11-13-2010, 08:12 PM
Did you change any plumbing lines? If not then maybe you put in worn out DI resin. The DI should bring the water to 0 regardless of any other problems.

BlueTang<3
11-13-2010, 10:23 PM
well i just went back and looked it took 4 hrs of running to bring it to 0 weird it is usually minutes.

Myka
11-13-2010, 10:37 PM
That's weird. When is the last time you checked the calibration of your TDS meter? Probably not your problem, but a good thing to check.

Hillegom, DI resin will only take out 20 ppm TDS.

BlueTang<3
11-13-2010, 10:46 PM
Never how do u check that ?? Ps i have cut your montis send me a pm well chat.

Myka
11-13-2010, 10:50 PM
Buy 342ppm sodium chloride calibration fluid. Make sure it is at the correct temperature (see the label) when you test.

PM to be sent.

hillegom
11-15-2010, 11:50 PM
Hillegom, DI resin will only take out 20 ppm TDS.

No, I don't think so. I have read that it will take out more.
The DI is the last filter and will take out whatever it receives. The more tds the DI gets, the faster it will be depleted. Thats why you use the RO filters to take out most of the tds.
I have looked for the original article where I learned this but have been unable to find it. But I did find this:
http://www.airwaterice.com/category/z.2/
Read down to Can a DI Cartridge be used as a standalone?