Fresh water tank problem

[spooled05]

When I'm connected to water at the R/V park its filling my fresh water tank and leaking out the fill , is there a valve somewhere I'm supposed to shut?
Ive looked over the water connection and also the pump for the fresh tank and theres nothing.

Thanks ,Zack

[BFlinn181]

It's according to how your RV is plumbed. Some RVs have a separate connection for 'city water' and a gravity port to fill the water tank. In that case, the only way water would get from the city water line to the water tank would be through a leaking check valve at the water pump. Another symptom of a leaking check valve is you'll notice that when using the pump, it has to cycle on even when no one is using water due to the leak down of the water pressure back into the water tank.

If instead, your RV has a single connection for water, then you have a selection valve that either pressurizes the plumbing system (city water) or fills the water tank. If that valve leaks back into the water tank that can cause over-filling over time.

One caution, if you have the selection valve type system, even if the valve doesn't leak it might overfill the water tank by a leaking check valve at the pump as mentioned above.

Often the check valve is built into the water pump, you'll have to see if the check valve is available as a separate part or rebuild kit. If not replaceable, you could install a separate check valve in the supply line from the water tank to the pump.

[spooled05]

Thanks!! In the owners manual it says its supposed to bypass the pump when on city water , I guess the check valve is not there or working. the fresh water tank was empty when I hooked up and it was leaking out the fill when I got back. Ill look into the pump , it does cycle alittle every once in a while when I was testing it before I left.

[BFlinn181]

Originally Posted by spooled05

Thanks!! In the owners manual it says its supposed to bypass the pump when on city water , I guess the check valve is not there or working. the fresh water tank was empty when I hooked up and it was leaking out the fill when I got back. Ill look into the pump , it does cycle alittle every once in a while when I was testing it before I left.

The city water does 'bypass' the pump, but it doesn't stop water from flowing backwards to the pump. Sounds like your check valve.

I hope you've also learned a valuable lesson, Don't leave the water on when away from the RV. Nobody's there to use it OR turn it off if it starts leaking. We never drive with the water pump on either, there are switches to turn the pump on when you're near a water source. Last year on iRV2 there was a sad story of a new RV owner driving down the road with the pump on, a leak pumped many gallons of water into his electronic's bay and caused great damage.