Thor Forums

[bevedfelker]

I'm not familiar with the Kantleah 4 way switch since my Vegas doesn't have anything like it. I've had this happen about three times. Every time I just turn off city water and run my pump for about two or three minutes. Turn off pump and turn city water back on and the problem usually goes away.

I think there is a check valve in the pump that sticks and allows city water back pressure to get through the check valve and flow through the pump backwards into the fresh water tank. The check valve is not external to the pump and mounted in the cold water supply line. The check valve I think is sticking is internal to the pump. The only way to change this check valve is to replace the pump. Since the problem usually corrects itself for a while before repeating, I've just learned to live with it and to periodically check the fresh water tank level on the monitor panel to see if the check valve is stuck again. That's way cheaper than changing the pump.

If one of the positions on that 4 way switch allows city water to fill the fresh water tank, that is where I'd start looking if nothing else is stopping the backward flow of water into the fresh water tank.