On 10/31/2019 at 11:26 PM, Steve1947 said:

I’m having a related issue.

Welcome to the Escapee forums! This thread is pretty old so you may need to start a new one with your question, but I'll do may best to help and perhaps others will join in.

The problem of the water tank getting full when connected to city water is probably that the pump is leaking back as it normally acts as a check valve when not in operation and yours seems to leak back. That can be resolved quite easily by adding a check valve to the water line between the tank and the pump. If you tank fill valve is open when not connected to city water that would cause your water pump to run continuously or if just leaking it would cause the pump to cycle on and off. The reason is that it then allows water that is drawn from the tank to be pumped into the water system, then to pass through the leaking fill valve and then return to the top of the water tank. Let us know if anything suggested here should help you.