Turn the water pump on when you flush the toilet.
If you have a coach with an electric switch to flush the toilet then this project might be for you. Flushing the toilet in this case depends on the water pump being on and occasionally (often for some of us) one might forget to turn on the water pump before needing to flush the toilet. Even though there is a water pump switch in the bathroom it is a bit of a reach from the throne of contentment. This add-on circuit using two common Bosch style relays will turn on the water pump if it is not on when you press the flush switch. It is configured to do nothing to the water pump if it is already on.
The wire colors in the schematic may be different depending on the relay sockets you use.
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Add it to your coach if it appeals to you.
I knew you would figure a way to get it to work with the water pump on.
Roger, clever circuit and a good idea...
Two of my coaches had a pump switch in the bathroom.
John, our coach has a water pump switch in the bathroom too, a bit of a reach while otherwise engaged.
Chuck, it took a bit of thinking to do this with simple parts. Less than $5. As with all of my projects they are done to improve livability in our coach for us.