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Fresh Tank Fills by Itself 1.2

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For the comment to add a check valve on the suction side of the waster pump when the pump check valve is stuck open. I was under the impression that check valves were always installed on the discharge side of a pump. Is there something different about travel trailers to have the check valve on the suction side of the pump?
danemayer
danemayer
In this situation, if you put the check valve on the output side, here's what may happen.

After you close the faucet, the pump runs just long enough to build pressure and activate the pump's pressure switch so it stops pumping.
The pressurized water leaks back through the pump reducing the pressure.
The pump pressure switch detects the loss of pressure and starts the pump, which runs long enough to rebuild pressure.

Depending on the amount of backward flow the pump is allowing, your pump may run quite intermittently, or quite frequently.

Putting the check valve on the supply side eliminates this problem.
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