when/how to change DI resin

[PapaKlix]

i bought my filterguys ro/di unit used from another RC member and have probably produced about 100 gallons. the guy who sold it to me said it was probably about time to change the filters but thus far i have not and the unit has produced 000 ppm on the outgoing tds meter (180-200 on the inbound). just now, it just started reading 1 ppm. color changing di resin is about half way amber. i was going to change the carbon/sediment filters anyway (based on the seller's recommendation) but should i change the DI resin as well? should i always plan on changing out the filters/resin when tds breaks 0?

i know i had read somewhere that you need to really pack the DI resin tight, i have pre-packed DI resin packages from the filterguys... so basically, just get it all in there?

[Michael]

i usually change the resin every 5-6 months, and the filters last a little longer i think, basically you need to connect the tds meter after the filters and when you see the tds rising you know they need changing, and when the tds gets to 2 or 3 after the resin that needs replacing.

i wash out the resin chamber and just pour in the resin beads, basically i use an old wooden spoon and with the handle keep prodding the resin down into the chamber to pack it in, its easy enough to do.

[Toddrtrex]

For me, I change my DI resin when the TDS gets above 2. And to tell that it is the resin that is bad, and not your RO membrane, just calculate if the RO membrane is still giving you close to its rated rejection rate.

My RO membrane is rated for 96-98% rejection rate. My incoming tap is about 160. So as long as the water right after the RO membrane has a TDS of 4-7 I know that the membrane is still good, and it is my DI resin that is exhausted.

[PapaKlix]

thanks guys