Leaking Swan?

[thesoundguy]

Got a question about the Swan filler valve that either fills the on-board water tank or provides city water.

Mine is almost always set on city water because I do extended stays in RV parks.

I took the motor home to be serviced at a local RV repair shop about 12 miles away after sitting in an RV park for about a month. I parked the coach on a slight tilt, went in to talk to the manager, and when we came back outside the fresh water tank overflow hose was draining on to the pavement. We noticed the tank was full and drained off some of the excess to stop it draining while inside the garage.

Here's the funny thing. I usually keep no more than 1/2 tank of fresh water on the rig, and keep the valve set on local water setting.

Could the Swan valve have been letting a little water at a time sneak into the tank to fill it? It's not leaking visually on the outside, but maybe internally That's the only thing I can think of as to how it got topped off. The water pressure is high at this park, but I do have a regulator on before the coach valve, set at about 45-50lbs.

Guesses, suggestions, kind words?

Image would only post horizontal and not vertical. Sorry.

[billb3672]

I have a different valve, but had the same issue on my 2014 42qd tour. I finally figured out that if you place the valve (completely) in the fresh water position it leaks by the valve and slowly fills the tank. To correct this, I just turned the valve to tank fill position and listened to the water flow, then moved the handle slowly to fresh water position until the flow sound stopped. This seemed to seal the flow, so the water didn't flow to the tank. These valves are poorly/cheaply designed. I will install a good brass ball valve to correct this design flaw.

[mccrob]

The Swan valve is a brass ball valve, I'll bet your problem is in your water pump the check valves in the pump head get week or get some dirt in them letting water from the park fill bypass the pump and go to the fresh water tank. Try shutting off the line from the tank to the pump and see if that fixes the problem