DI Question

[maroun.c]

Can you please share after how many gallons or maybe roughly every how often do you change your DI? as well as what TDS do yo uhave going into it?
Thanks

[PurdueWaterGuy]

If you know the TDS of the water coming out of your RO, and the capacity of the DI cartridge (usually in grains or kilograins or kgr) you can figure it out for yourself. The conversion factor is 1 grain = 17.118 ppm.

In big commercial systems we use two DI beds in series and watch the purity of what's coming out of the first bed. Whe it starts to rise, you remove the first bed, move the second bed to the first position, and put in a new second bed. That way you are assured of always having quality water.

Our system at work has a pair of 15 cubic foot beds in the rough loop and a pair of 30 cubic foot beds in the polish loop. We buy our ion exchange resin in 5 or 7 cubic foot barrels. Don't let the resin out of the cartidge, it's like walking on microscopic ball bearings....

[thegrun]

If you know the TDS of the water coming out of your RO, and the capacity of the DI cartridge (usually in grains or kilograins or kgr) you can figure it out for yourself. The conversion factor is 1 grain = 17.118 ppm.

In big commercial systems we use two DI beds in series and watch the purity of what's coming out of the first bed. Whe it starts to rise, you remove the first bed, move the second bed to the first position, and put in a new second bed. That way you are assured of always having quality water.

Our system at work has a pair of 15 cubic foot beds in the rough loop and a pair of 30 cubic foot beds in the polish loop. We buy our ion exchange resin in 5 or 7 cubic foot barrels. Don't let the resin out of the cartidge, it's like walking on microscopic ball bearings....

I do the same with my home unit. Our city water is primarily well water around 450 TDS. A single DI cartridge will only reduce the TDS to about 20 PPM, so I run two cartridges in series, when my TDS starts to rise, I remove filter #1, move #2 into the old #1 slot and add a new filter in the #2 slot.

[PurdueWaterGuy]

I do the same with my home unit. Our city water is primarily well water around 450 TDS. A single DI cartridge will only reduce the TDS to about 20 PPM, so I run two cartridges in series, when my TDS starts to rise, I remove filter #1, move #2 into the old #1 slot and add a new filter in the #2 slot.

Without RO? That's a lot of ion exchange resin to be sending to the landfill...