High TDS

[labragg1]

I just installed one of your 4-stage units for one of my clients.

Tap water TDS is about 370

After hooking it up i ran a few gallons through it and then checked TDS--it tested 0.

Client has a 400gal system so the unit ran solid for about 3 to 4 days filling up the tank.
When I can back in after it was full I checked the TDS coming out of the unit and it was 34ppm.

Any thoughts on why it went downhill so fast?

Only thing I could think of was maybe the water pressure--it is steady at about 40psi.

Any help would be appreciated.

You guys are the best!!!

[BuckeyeFS]

With the high tds feed water, combined with low pressure (= less than ideal rejection), you may not be that far from what should be expected.

I'm wondering if high CO2 also caused an issue.

Russ

[labragg1]

Would increasing line pressure help very much? What would be a reasonably priced way to do this?

THanks

[BuckeyeFS]

It should, especially if you are using the 150 gpd membrane. 40 psi is really very low. 10 psi below spec for the 50, 75 and 100 gpd membranes, and 20 psi below spec forthe 150 gpd membrane. A booster pump is what you'd want to raise the pressure. Even small changes in the tds in the permeate with affect resin life span. The effect on resin life span becomes more and more pronounced as tds levels in the permeate approach zero.

Russ

[labragg1]

Ok--could you pm a price on what the appropriate pump would run? THanks

Oh--and it's a 100gpd membrane.