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augustpilot's avatar
augustpilot
Explorer
Feb 19, 2018

City water filling fresh tank

My trailer fresh tank fills direct on side of trailer. Tank is full. Left for week and turned city water off. Came back today and turned city water on, then while walking outside noticed water coming out the water fill overflow. Water is somehow going under pressure into fresh water tank. The water pump is new. Was working fine until turned off water pressure for week. Help please.

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  • Artum_Snowbird's avatar
    Artum_Snowbird
    Explorer
    Feb 19, 2018
    Take the city water off and run the pump. If flow seems weak and pressure does not build up, you have the valve that others mention. I had one like that. It needs to be in the off position to prevent tank fill, and to allow pump pressure to build up when on pump only. If in the fill position when on pump, water just recirculates back into the tank and out the pump again.

    good luck.
  • Farmboy666's avatar
    Farmboy666
    Explorer
    Feb 19, 2018
    ScottG wrote:
    It can only get in the tank through the pump. There is no other avenue from the city water connection to the fresh water tank.

    You could:
    Replace the pump
    Take pump apart and rinse all parts off. This may fix it.
    Install another check valve
    Install a manual valve

    Not true, my tank is filled from city water connection and has nothing to do with the pump, I have to open the tank valve to fill tank or close it to use city pressure.
  • D_E_Bishop's avatar
    D_E_Bishop
    Explorer
    Feb 19, 2018
    If the water is trickling out of the overflow, I would direct my attention to the check valve in the pump head. If it is blasting out, your city water fill valve is open.
  • Lynnmor's avatar
    Lynnmor
    Explorer II
    Feb 19, 2018
    You may have a valve to pressure fill the tank, if so it needs to be turned off. As above, the check valve in the pump may be faulty.
  • Lwiddis's avatar
    Lwiddis
    Explorer II
    Feb 19, 2018
    Using city water only to refill the fresh water tank is the safest method.
  • ScottG's avatar
    ScottG
    Nomad
    Feb 19, 2018
    It can only get in the tank through the pump. There is no other avenue from the city water connection to the fresh water tank.

    You could:
    Replace the pump
    Take pump apart and rinse all parts off. This may fix it.
    Install another check valve
    Install a manual valve

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