Is this DI resin done?

[howaboutme]

Your water company can tell you if they use chloramines and, if they use it seasonally, how you get information about when they switch over to it and away from it.

 

Technically speaking, chloramine (NH2Cl) is not filtered out by activated carbon, but the carbon acts as a catalyst to break it down as follows:

 

NH2Cl + H2O + C* ==> NH3 + Cl + H + CO*

2NH2Cl + CO* ==> N2 + 2Cl + 2H + H20 + C*

 

Where the asterisk helps you track the activated carbon used as a catalyst. It's the intermediate ammonia product (NH3) that can cause damage to your RO membrane (it can degrade polyamide-type membranes). Thus, to mitigate the damage, you want to extend the contact time with the carbon so that more of the ammonia is converted through the second reaction.

 

Wow, Tom! This is great! I've always known that you can control chloramines w/ a low micron (1 or less) carbon filter but never grasped the reason or science behind it. I'm going to save this for future reference. Thanks for being such a great resource.

 

So...Dj...since your DI is new, I would replace your RO first because your after RO TDS is very high. It should be less than 10. Then retest. And next time you replace your carbon and sediment, get 1 micron or less, not the 5 that BRS usually sells...This way, you don't have to add an additional stage to your RODI setup.

[Origami]

Kinda' like Ethanol is gasoline?

Insofar as seasonal use, yes. But for different reasons. For example, Fairfax County Water Authority uses it routinely, but in the Spring, when they flush their mains, they switch back over to chlorine which more aggressively oxidizes organics. Here's a statement from their site:

 

"Chemicals called disinfectants are added to drinking water at the treatment plant. Fairfax Water’s primary disinfectant is chlorine and its chemical compounds. Chloramine, the combination of ammonia and chlorine, form a stable bond that keeps a disinfectant residual throughout the entire distribution system. During the spring months, Fairfax Water performs its annual flushing. While that program is in progress, the disinfectant is changed to free chlorine. Free Chlorine is an aggressive disinfectant that aids in the disinfection of the flushed water mains. Fairfax Water is also beginning to utilize ozone as a disinfectant. The use of ozone will allow the amount of chloramine and free chlorine added in the treatment process to be reduced."

[Origami]

Wow, Tom! This is great! I've always known that you can control chloramines w/ a low micron (1 or less) carbon filter but never grasped the reason or science behind it. I'm going to save this for future reference. Thanks for being such a great resource.

 

So...Dj...since your DI is new, I would replace your RO first because your after RO TDS is very high. It should be less than 10. Then retest. And next time you replace your carbon and sediment, get 1 micron or less, not the 5 that BRS usually sells...This way, you don't have to add an additional stage to your RODI setup.

DJ, if you do change out your membrane, remember that Air, Water, Ice - one of our sponsors - has a special running through June: 35% off RO membranes. See this link for details.

[NateCamReef]

There is a rubber seal on top of the DI reservoir before you screw it on. If that got taken out in the process of changing the media, that can lead to a quick exhaustion of the new media.