9100SXT Twin Tank not working on tank 1

[Kevin Martin]

I have a 9100SXT twin tank system and it ran out of salt a couple of months ago. After recharging, tank 2 is soft and working fine, but when the unit switches to tank 1, you can tell instantly and the water is not soft in the least. Anyone know what I need to look for or how to fix this? Unit seems to cycle fine on both tanks. You can see the brine draw functioning like it should, but tank 1 is never soft.

 

[ditttohead]

The tank number is controlled by the lower piston. You can tear the valve apart and inspect it but if you are going to do that you should simply rebuild the valve. Also consider removing the head from both tanks and inspecting the resin level and quality. Check the riser o-ring etc. A quick valve tear down should quickly reveal the problem.