Forum Discussion

Two_Hands's avatar
Two_Hands
Explorer
Apr 10, 2015

Fresh Water Tank Problem

We left home with 1/3 full fresh water tank. Got to the rv park and hooked up to city water. All was fine for three days. Next morning I see water dripping out of our fresh water fill spout. I check and find out I now have a fresh water tank that is over filled and running out the spout. What the heck happened? My ignorant guess is that the bypass valve has malfunctioned. I have never used it. If that is the case how could it be repaired? Any other thoughts on what could have caused the problem? Thanks in advance.
Class A

8 Replies

  • Two_Hands's avatar
    Two_Hands
    Explorer
    Apr 14, 2015
    I think mccsix wins the prize. I made sure the city water/fresh water tank valve was set properly and the problem seems solved. Thanks everyone for all of your responses.
  • mccsix's avatar
    mccsix
    Explorer
    Apr 10, 2015
    Ensure fill/city water selector handle is full over to city water, don't go by the markings, you have feel the valve and it may have to go past the line on the panel. .
    If I set my handle exactly on the line for cw/ it will still allow a small amt of water into the tank and overnight it will over flow
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Apr 10, 2015
    Water pump has an internal check valve....stops water from flowing back thru pump into fresh water tank.
  • wildmanbaker's avatar
    wildmanbaker
    Explorer
    Apr 10, 2015
    Fleetwood usually have a manual valve to open or close to fill the fresh water tank from the shore water. Dennis and others probably have the answer. The pump is most likely the problem.
  • Dennis_M_M's avatar
    Dennis_M_M
    Explorer
    Apr 10, 2015
    It's either a fill switch as noted above OR, and most likely, the check valve in the water pump (not the city water connection) that is bad.

    Easy way to check, disconnect the inlet side of the water pump and see if there is leakage while on the city water.
  • Jack_Diane_Free's avatar
    Jack_Diane_Free
    Explorer
    Apr 10, 2015
    Just a fauly check valve in the city water intake. Easy to replace. Ours did the same thing.
  • rk911's avatar
    rk911
    Explorer
    Apr 10, 2015
    Two Hands wrote:
    We left home with 1/3 full fresh water tank. Got to the rv park and hooked up to city water. All was fine for three days. Next morning I see water dripping out of our fresh water fill spout. I check and find out I now have a fresh water tank that is over filled and running out the spout. What the heck happened? My ignorant guess is that the bypass valve has malfunctioned. I have never used it. If that is the case how could it be repaired? Any other thoughts on what could have caused the problem? Thanks in advance.


    our freshwater connection on the MH has a switch...CITY WATER/FILL TANK. does yours have something similar? otherwise I'd guess a bad check valve.

About Motorhome Group

38,763 PostsLatest Activity: Dec 05, 2025