Issue with water filling fresh water tank

[rswitzer1]

I have a 2008 Holiday Rambler Savoy TT and I am having an issue with water filling up fresh water tank while connected to city water. This issue has just started happening. I already replaced the pressure check valve on the city water inlet and also the water pump because I thought maybe the internal check valve went bad but no luck. Still have the same issue. This should be a simple fix but can't figure it out for the life of me. Any ideas? Need more info?

 

[MapNerd]

What exactly is this issue? Water not filling? Filling slowly? Overflowing? Something else?

 

[rswitzer1]

If I keep the fresh water tank valve closed, it will continue to fill up even when connected to city water. Naturally, if I keep the valve open, it will just keep running out.

 

[MapNerd]

I’m unfamiliar with HR water so just poking in the dark, but do you happen to know if you have an auto-fill functionality where the valve opens and closes automatically based on tank level readings? I had a sensor strip go bad and the tank would overfill because the sensor strip wouldn’t read that it was full.

also possible might be that your autofill solenoid, if equipped, has gone bad

Often, those fresh water tank valves are not actually shutoff valves but diverters that redirect water to through one fill mechanism or another - for example autofill or manual fill, and the actual shutoff is done by the mechanism downstream of the valve.