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Midgepingleton's avatar
Midgepingleton
Explorer
Jun 03, 2017

Black Water Tank filling and overflowing

Hey y'all. I'm in my second travel trailer. (Used to live in a 5th wheel and now have a tag along Nomad). In my old one I never used the toilet. I don't need the toilet here either but for some crazy reason the toilet keeps filling with water and overflowing! The black water tank is filling by itself? I thought at first it was too much pressure from the well water so I bought a regulator and it didn't solve the problem.

Grey water seems fine but then again I have the grey water line open and it's just running out (I'm on a farm) I have a composting toilet outside.

Any suggestions? Is there any way to install a shut off valve somewhere between where the city/well water goes to black water system?
M

10 Replies

  • Bobbo's avatar
    Bobbo
    Explorer II
    Jun 04, 2017
    I sincerely wish my new trailer was plumbed with the bathroom sink into the black tank. My old Winnebago was and it made it super easy to add water to the black tank to fill it up for dumping.

    I may actually replumb my new trailer.

    To put this on topic, OP, I bet your bathroom sink is plumbed into the black tank.
  • KrowNB's avatar
    KrowNB
    Explorer
    Jun 03, 2017
    LadyRVer wrote:
    One unit I had the bathroom sink drain, not the shower, drained into the black tank. Called the mfg. Customer Service and the model I had was the only model of theirs plumbed like that.

    Mine's plumbed like that: bathroom sink and toilet into Black; shower into Grey1; Kitchen sink into Grey2.
  • Sam_Spade's avatar
    Sam_Spade
    Explorer
    Jun 03, 2017
    NMDriver wrote:
    You can plug the toilet feed line.


    For that to be the problem, the flush seal in the toilet would ALSO have to be bad......or else it would be the toilet that would fill and overflow, not the tank.
  • LadyRVer's avatar
    LadyRVer
    Explorer II
    Jun 03, 2017
    One unit I had the bathroom sink drain, not the shower, drained into the black tank. Called the mfg. Customer Service and the model I had was the only model of theirs plumbed like that.
  • NMDriver's avatar
    NMDriver
    Explorer
    Jun 03, 2017
    You can plug the toilet feed line. Just disconnect it from the back of the toilet and go buy the appropriate size plug or cap depending on whether you have male or female threads.

    If, as suggested by the above posters, that does not fix the problem then one of the other water sources, Grey or Black flush, is your problem.
  • Sam_Spade's avatar
    Sam_Spade
    Explorer
    Jun 03, 2017
    Midgepingleton wrote:

    Any suggestions?
    M


    Yes. Keep it simple.

    If you are absolutely sure that there is no "waste" going into the black tank, just leave that valve open too. Problem solved.

    If you want to know what is happening for future reference, close the grey valve, disconnect the hose and post somebody outside to watch the discharge point while you go around inside and run the shower and sinks one at a time to see which one is plumbed to the black tank.

    There should NOT be any direct connection from the fresh water line to the tank (except maybe for the aforementioned tank flushing system).
  • BB_TX's avatar
    BB_TX
    Nomad
    Jun 03, 2017
    Do you have a black tank flush system, and have it connected to your water supply?
  • Dick_B's avatar
    Dick_B
    Explorer
    Jun 03, 2017
    My guess is that the shower is plumbed to the Black Tank since more shower water is used than kitchen water.
    Would you like to crawl under to see what is what?

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