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eocamper's avatar
eocamper
Explorer
Jul 13, 2015

Black water tank flush

I seem to get water leaking into my tt while flushing my black water. It comes out of the check valve under the sink. What am I doing wrong? Maybe I turn the pressure on too high? The drain valve/plunger is always open. Thinking about removing the check valve and running direct. Any thoughts, advice.
My tt is a 2015 Grey Wolf 26bhe.

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  • MFL's avatar
    MFL
    Nomad II
    Jul 14, 2015
    I agree, they are problematic. If you are using really high pressure, you could be causing the leak, as the preventer valve will slow the flow, and could cause leaks at the fittings.

    I see you are in Tx, but if you were storing in cold weather, you need to blow out the flush line to keep the valve freeze protected.

    Jerry
  • BB_TX's avatar
    BB_TX
    Nomad
    Jul 14, 2015
    You are not doing anything wrong. Those anti siphon/back flow preventer valves are common failure items. Time to replace it.

    Removing the valve is an option. But you need to use an external back flow prevention valve if you do to prevent the unlikely, but possible, backflow of water into the fresh water source.

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