RO/DI filter question...

[afboundguy]

I was aimlessly looking at sites today while stuck at work and was looking on an RO/DI site and read that the carbon blocks should be changed out every 6-12 months... I know everybody is different depending on TDS of tap water but I always though to replace them all when the pressure starts dropping correct or is that just for the sediment filters? I'm just double checking as my brain's not working properly

 

[Glenn E King]

Carbon blocks

My experience is that the carbon block often plugs up before it looses its filtering capability.
As you said when the pressure drops the carbon blocks are suspect.
To determine which component may be blocked and causing the pressure drop you can pull the filters one at a time and see which one restores the pressure.
Of course, the TDS reading of the out put is the real key.

 

[frank180reef]

my TDS meter that is hooked up to my RODI read zero, I borrowed a friends and his hand held read 6. I replaced the carbon and it read 3,replaced the resin and it was zero...............

 

[stingythingy45]

I have both a hand held(cheapo)and inline one.I'd trust the inline first.
I generally check the tds before the di to see what the has climbed to,as that's ny drinking water side.