Making quality RO/DI with softened/neutralized Well Water?

Randy Holmes-Farley · Jun 11, 2016

BigJohnny said:
What about distilled water, is that okay to use until my RODI is fixed?

Typically, it is fine.

BigJohnny · Jun 14, 2016

Here's the latest plot twist, my tds is higher after the DI Resin than before........!

I got the booster pump and decided to replace my sediment filter/carbon block/di resin as well. Hooked everything up and the tds read 2 after the membrane, and 8 after the di cannister!

What could possibly be causing that except for a bad tds meter? I feel like bad di resin would simply not improve the tds, not make it worse! Help?!

BigJohnny · Jun 14, 2016

BigJohnny said:
Here's the latest plot twist, my tds is higher after the DI Resin than before........!

I got the booster pump and decided to replace my sediment filter/carbon block/di resin as well. Hooked everything up and the tds read 2 after the membrane, and 8 after the di cannister!

What could possibly be causing that except for a bad tds meter? I feel like bad di resin would simply not improve the tds, not make it worse! Help?!

Nvm it works now, weird

TheEngineer · Jun 16, 2016

Haha. I was going to say the resin might be depleted.

Randy Holmes-Farley · Jun 16, 2016

FWIW, TDS can easily be higher after a depleted resin than before, since the ions being released may be more conductive than those coming in and being retained.

BigJohnny · Jun 28, 2016

Randy Holmes-Farley said:
FWIW, TDS can easily be higher after a depleted resin than before, since the ions being released may be more conductive than those coming in and being retained.

So your saying it's normal for fresh resin to leave a higher tds count? It has to "break in" a bit?

TheEngineer · Jun 28, 2016

Maybe for the first few gallons. When the resin is depleted it starts breaking down and you will see higher TDS out of it than into it.

Randy Holmes-Farley · Jun 28, 2016

What I was saying is that depleting (old) resin can have higher TDS out than in. But more importantly, it can have higher values for specific items we want to remove, such as ammonia or silicate which are weakly bound and easily come off the resin when depleted.

Randy Holmes-Farley · Jun 28, 2016

Duplicate

BigJohnny · Jun 28, 2016

Randy Holmes-Farley said:
What I was saying is that depleting (old) resin can have higher TDS out than in. But more importantly, it can have higher values for specific items we want to remove, such as ammonia or silicate which are weakly bound and easily come off the resin when depleted.

Makes sense. In my case it was fresh resin increasing tds though. Shortly after my tds meter died so I think it must have been that.

Thanks for your input !

airwaterice · Jul 7, 2016

Yes...the batteries....Fresh DI resin will ALWAYS get zero tds...even the low grade DI resin that we REJECT multiple times a year... In Air Water Ice 's refillable 10" Nuclear Grade Mixed Bed Di Cartridge the spec is 6,000 but it will hold at least 3,000 ppm tds. The equation for how long your di will last...EXAMPLE:
1.) you have 300 ppm tds at your house...
2.)your RO tds is 15 ppm tds (95% rejection) ...
3.) take 3,000/15 and you will get 200 zero tds gallons before exhausting. Get your RO rejection down to 5 ppm and you will get 600 [3,000/5] zero tds gallons before exhausting (showing 1 ppm after making one gallon of RODI water).