Forum Discussion

JackInAZ's avatar
JackInAZ
Explorer
Apr 07, 2017

Overflow In Fresh Water Tank

In both my latest Class A's I have had what I think is a faulty fill valve. When connected to city water, this slowly causes the fresh water tank to fill and overflow. My dealer finds no problem although he says they have had a number of similar complaints. I suspect he did not find the problem with my coach because he did not connect with city water.

Anyone else have a similar problem and what should I do? Since the RV is still under warranty, should I complain to the service manager or ignore this because, in comparison with other potential headaches of RV ownership, this one is small potatoes.
  • NanciL wrote:
    I had the same thing and it was a defective check valve in the water pump, allowing the water to flow back from your city water pipes.

    jack L


    In my case, since I don't use the fresh water tank, I disconnected the outgoing pipe from the water pump and installed a valve in it and then just keep the valve off.
    Since the trailer is still under warrantee, I brought the water pump into the dealer and told them the check valve in it was defective. Naturally they said they had no means to test it and would have to send it back to Forest river. Two weeks later they called and I now have a brand new replacement, that I will probably never hook up.

    Jck L
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Well I have three recommendations. and a comment:

    First it might NOT be the quick fill valve.. it might be the water pump.. I will say no more on this except you may be able to demonstrate the problem by disconnecting from City water and turning on the water pump. If every so often it cycles... You have demonstrated there is a leak SOMEWHERE.. Options are

    Detectable leak (Drip, Drip, Drip)
    Water pump check valves
    Quick Fill (These last two will leak water back into the fresh tank so no detectable Drip Drip, Drip)

    IF NOT a warranty issue.. It is a standard 3-way valve, nothing special save the mounting, most Plumbing supplies can provide.. Fittings are 1/2 inch Pipe thread

    What I Will do IF my quick fill ever fails

    I will replace with a standard "T" fitting and keep a plug on hand in case (Standard hose fitting (male adapter with plug or cap) to screw into city water inlet if check valve fails.

    The "Through" on the "T" will likely to to the house

    The "T" to a quarter turn valve and from there to the fresh tank fill

    That way I can open the valve (Which is less expensive than the 3-way so cheaper to replace if it fails) and still have pressure to the house.. reduced it is true, but pressure.
  • I had the same thing and it was a defective check valve in the water pump, allowing the water to flow back from your city water pipes.

    jack L
  • If you have a 'Fill Valve' make sure handle is not just turning on valve stem....valve not fully closing

    Internal check valve in on-board pump can also be issue....diaphragm not closing allowing back flow


    Remove pump suction line at pump..turn on city water.
    Water comes out of pump suction connection...pump check valve
    Water does NOT---then Fill Valve
  • Dannyabear1 wrote:
    Mine will do that occasionally, run the pump sometimes it will re seat the check valve



    X2

    Or take the pump a part and clean the check valve.
  • Mine will do that occasionally, run the pump sometimes it will re seat the check valve