Why isn't my well treatment tank emptying as expected?

Question

I have a well system with a Chem-Tech XP peristaltic pump to reduce the sulfur smell in my water. I just bought the house so I don't have any history. The problem I am having is there is a 15 gallon tank that is a chlorine/water mix that the pump uses to reduce my sulfur smell issues. The pump is not working correctly because the tank never empties; it is always completely full, probably overflowing as well.

I did verify that the pump was pumping the mixture to the injector. The tank should go down as it injects the solution into my water system. I have already replaced the pump tube, it had a hole in it, and the injector valve. I was thinking the valve, which has a check valve to keep water from backflowing, was the issue. But it is still doing the backflow issue. Any help would be appreciated.

Answer 1

You've verified that the peristaltic pump is actually pumping to the injector. Have you verified that the injector is accepting and actually injecting the chlorine/water mix? It's possible for an injector to become corroded from the corrosive chlorine mix or to become clogged from debris.

You mentioned a check valve. They can also become corroded or they can leak from fine debris getting stuck in them. A backflow of just one drop every 30 seconds will add a gallon of water to your chlorine tank in 20 days.

To see if you are getting a backflow, you can disconnect the tubing from the chlorine tank, put the free end in a small container, and wait a few hours to see if water accumulates in the small container. If the check valve is in fact leaking and it's an integral part of an expensive valve, you can consider adding your own check valve to the tubing between the chlorine tank and the peristaltic pump. Use a check valve with Monel or Teflon (PTFE) working parts.

If you confirm backflow and eliminate it, you should consider discarding your chlorine mix and mixing up a fresh batch because you don't know how diluted it has become.

If you have not yet done a test for radon in your well water, it's time. I'm assuming that your water system has a large contact tank where the chlorine can neutralize the hydrogen sulfide, followed by a granular carbon filter to remove excess chlorine, and it backwashes periodically. If you have radon in your well water, that granular carbon filter has become radioactive and potentially hazardous.