Fresh H2O tank fills while supply connected to City intake

[Warren DR]

HELP please.
I connected the water supply hose to the city water connection on the trailer's connection panel. Once everything was hooked up, all was working fine. Later in the day I noticed water was pouring out of the fresh water tank overflow. All faucets still worked as expected.

Steps I took:
1) Turned OFF the city water and
2) Then turned ON the water pump with a faucet opening then closing it for a time then back on. I could hear the pump but no water coming from the faucet. I let the pump run for about 30 seconds. I'm not sure how long I should let a pump run without water running through it.

Any diagnosis and repair tips regarding my issue would be greatly appreciated.

[Jester]

I have had my impeller in the water pump dry up for lack of a better explanation. When this happens, pressurized city water can push by the impeller (which works as a one way valve as well) and begin to fill the fresh water tank. I noticed mine as I leave the fresh water drain open always and it started dripping. Let the fresh water tank fill for bit, turn off your city water and use the fresh water pump to let the water rehydrate the impeller. You can verify that the fresh water tank has water in it using your level indicators. Once you have run some water through it, open your fresh water drain and turn the city water back on. Once the fresh water tank has drained, you can continue observing to see if the fresh water drain continues to drip. If that doesn't solve the issue, you may need to either install a check valve or replace your fresh water pump.

[dutchmensport]

What is the make, model, and year of your camper? It sounds like you have a wet-bay or a convenience center for your water hook-up and valves. If so, make sure you flip the valve from "flill" to "run" or "normal"... however it's labeled, as long as it's not on "fill".

Second. Make sure your valve that says "Winterizing" is "off". If the winterizing valve is on, your water pump will suck air and you'll never get water .... unless you attach a hose and stick the other end of the hose into a bucket of RV antifreeze.

About the water pump itself. It does not hurt the water pump to run dry. I've had 4 different trailers and at times have found my water pump running for hours and hours with no water in the fresh water tank. It never hurt the water pump at all. It hurt my pride.... but not the water pump!

Check those valves: Winterize valve = off. Water heater by-pass = off. "Fill / run" = set on "run" ... NOT on Fill.

You only put that valve on "Fill" when you are actually "filling" the fresh water tank. Once it is filled, you flip it back to the other position to use either the on-board pump, OR to continue using the garden hose (shore water) supply.'

Also, if using shore water (the garden hose) ... turn the water pump off. You don't want it on.

[Panhandlerv]

hey guys, I have a 2022 cougar 32 rli with the same problem as Warren Dr water hose from well hooked in the only connection on my setup,other than black tank flush. pressure regulator on my hose or disconnected doesn't matter. I have a blue valve that has 2 selection.. city water or fresh tank fill.
my fresh water tank fills up and runs out overflow at about a 1/4 of my water pressure. so I replaced the 2-way valve with blue handle. does the same thing.
my water line from city water side of valve runs straight to water pump and straight out.
so, there must be a check valve some where beyond water pump that backwash's thru the water pump pickup tube.
how or where would i find a plumbing schematic.


Thanks Allen