Fresh Water Filling Up by itself?

[Kchamp40]

3011DS so confused. Our freshwater tank was empty. We got to a campground and plugged into city water inlet. Next day we see water dripping on ground and coming out of fresh water tank. We turn off city water connection to RV and run water thru facets to drain fresh water tank. It fills back up! Only water connected to RV is at the city water connection . Water pump appears to be a bit more noises. Any ideas?

[benchmarks]

I’ve never experienced. Only way I can get water into my freshwater tank (that I know of) is to add to the freshwater inlet. The pump has an inlet and outlet check valve built into the pump head or line. Probably a piece of dirt or plastic shaving stuck in it maybe.

[benchmarks]

My 2 cents....shut off water and turn on pump and run it for a few. Turn city water back on and drain the tank.

[sgtlm17]

Originally Posted by benchmarks

My 2 cents....shut off water and turn on pump and run it for a few. Turn city water back on and drain the tank.

X2 your check valve on pump is probably stuck and city water is passing through to FW tank. Using pump may make it seat properly.

[Cypressloser]

Could also be a valve on the water distribution panel leaking back into the FW tank, open and close these valves several times, see if that helps. Worst case scenario is a defect tank fill valve that needs to be replaced, under warranty I assume.

[SlfMdeFam]

I had this same issue this past weekend and posted it on here. The response i got was the same and it worked. Turn off city water. Run the pump for a few minutes. Turn city water back on.

[Coha]

I too had the same problem and resolved it by turning off the city water, turning on the water pump, and bleeding the pressure at the farthest faucet. This in turn allowed the bypass on the pump to re-seat itself.

[JimMorrell]

Back flow device in your on board water pump is not functioning. I had to replace the pump. When you hook up to city water, the pressure sends water backward through the pump and in to the fresh water tank.

[5picker]

You've received many correct responses about the check valve built into the water pump.

I'll add... make sure you are using a QUALITY water pressure regulator on your city water connection.
You also mentioned the pump is somewhat more noisy.
You may know this but your post was a little confusing, the pump is not to be on when connected to city water.

One last thing... you don't necessarily have to turn the pump on to eradicate the water from your fresh tank... just open the tank drain.

[Flybob]

Follow suggestions above. Do not use the FW pump when connected to city water. it can cause the check valve to re-seat improperly.

[rcla2014]

Originally Posted by benchmarks

My 2 cents....shut off water and turn on pump and run it for a few. Turn city water back on and drain the tank.

X3! There is a check valve on the output end of the fresh water tank pump. If you accidentally use the water pump while hooked up to city water, sometimes the check valve will remain open and allow pressurized city water to go through the, now open, check valve and fill your tank. When that happens to me, I use the freshwater tank water to fill the gray water tanks (just shut off city water and turn on water pump and let the water in sinks run until the gray water tank(s) fill) just before dumping. That way, you're sure to have enough gray water to flush your hose.

[Goodnabor]

I also had this same problem with my R-Pod and I think the problem may have been caused by not having the by-pass valve on the hot water heater in the closed position last year but then I am having a problem tracing the path of city water through that valve into my tank, so that my not have been it. The only other thing I can think of is I took my water pump out for winter last year, cleaned the screen/filter, and reinstalled it in March, and I didn’t have any problem with my fresh water filling when hooked up to city water this season.

[rebeltown]

If you rarely or never use your fresh water tank then put a shut off valve in the line. Then if your check valve ever fails again it will not over flow your fresh water tank and make a mess of your trailer/RV. If you need to use your fresh water tank simply open the shut off valve.

[ptylerp]

X2 on pressure regulator on city water inlet line.

I use a water regulator set to ~40 # works well. Any pressure above that and I notice leakage back thru the water pump check valve.

[Fiddler Dan]

I have had the same problem with 2 different travel trailers. You probably have a Shurflo 4008 water pump. I have not found a solution.

[jackconn]

All great advice. I had the same problem and only discovered it after driving the trailer with a full FW tank, which bent one of the support bars holding up the tank. Fortunately not a disaster but could have been. One other suggestion: I added a ball valve to the line after outlet from FW pump, which will positively shut off the line back to FW tank. Easy mod and easy to reach when I'm on tank vs. city water.

[Olean Mike]

I have experienced the same problem on a couple of occasions. You have received good advice as it has worked for me. Evidently this is a quality issue if so many have experienced it. I even had a service man say that couldn't possibly happen. Sounds like they know but don't want the hassle of a recall on the pumps.

[Hodie Ho]

5picker is correct about the pressure regulator. We had the same issue with the tank filling on its own. We changed the pressure regulator and the problem was resolved. We now have a regulator with a dial we can set to the pressure we want. No more problems.

[guardingliberty]

Originally Posted by rcla2014

X3! There is a check valve on the output end of the fresh water tank pump. If you accidentally use the water pump while hooked up to city water, sometimes the check valve will remain open and allow pressurized city water to go through the, now open, check valve and fill your tank. When that happens to me, I use the freshwater tank water to fill the gray water tanks (just shut off city water and turn on water pump and let the water in sinks run until the gray water tank(s) fill) just before dumping. That way, you're sure to have enough gray water to flush your hose.

This exactly happened to me....I accidentally hit water pump. It stuck opened. It half filled my water tank before I discovered it filling up. I shut off the city....ran the pump for awhile... shut it off.... now it’s all good! Thanks

[JimMorrell]

And then there is the occasional water pump failure. My new at the time TT experienced the problem. It required a brand new water pump. That's probably the most common problem.