Jack Valance wrote:
I did replace the switch and it did the same thing. ...

Like in a very short time, you mean?

In that case, it's not the relays or switch itself.

I'd look at the pressure pipe connection where the switch is mounted.
I'd venture you've got corrosion/sediment collected in that 1/8" pipe
that is not giving good pressure reading; knocking on it disturbs enough
for it to operate again for a little while...

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