Pump Check Valve or Bad City/Fill Valve

[memphisflyer]

I have a 2000 Allegro Bay. When I have the City/Tank Fill valve in the City position, all is normal inside with good pressure but water slowly flows into the fresh water tank. After about 5 hours, the tank fills and overflows. For a temporary solution, I just close the supply and work off the tank for a bit. Also, when I turn on my pump, it runs intermittently for about 3 or 4 seconds and then stops for half a minute before starting again. I'm assuming these are related since I have no water leaking anywhere. Is this likely a bad check valve or pressure switch in the water pump? Or could it be a bad City/Tank Fill valve letting some water into the tank? Any help would be greatly appreciated as I've only been an RV owner for two weeks (but I', loving it).

[RV Wizard]

You have a bad city/fill tank valve. When the pump is turned on it i flowing back into the fresh water tank.

[memphisflyer]

Thanks, I thought that was likely it when the tank was filling. The thing that threw me off was that with no water entering the unit (supply turned off) the pump runs intermittently. I wasn't sure if that was a separate problem. I'll replace the valve. Thanks again.

[RV Wizard]

You are welcome.

[memphisflyer]

I just replaced the City Water/Tank Fill valve with a new valve from Tiffin with the exact part number. The good news is that the pump no longer runs intermittently (only when it's supposed to) when working off the tank. However, I still have water slowly entering the tank when using a water hook up and the valve is in the "City" position. Any ideas? Thanks for any help you can give.

[RV Wizard]

I would suggest that the valve be removed and inspected for any debris that may have gotten into it; such as any Teflon tape or pipe dope. If nothing is evident then a bench test of the valve is necessary. If the valve is defective contact Tiffin for a new one under warranty.