I have a manual bilge pump now and plan on installing a new automatic pump. I saw a recommended wiring diagram which would require that I change the two-way switch (On/Off) on the dash to a new three-way switch (On/Off/Auto). A diagram of the suggested wiring is attached.

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It worries me that if the switch on the dash isn't set to Auto, the pump won't run and my automatic pump won't be automatic. I thought a better way to wire the pump would be in this second diagram (hand drawn).

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This way the pump will run if the boat starts to fill up with water, regardless of whether I forgot to leave the swith in the Auto position.

I'm wondering if I'm missing anything and if anyone has any input to what I think is a better approach. This way I also don't have to find a new three-way switch to fit in my dash where the existing two-way switch is now.

Any comments appreciated.