Originally Posted by Davie
Yes, its to do with the auto pump. Design fault but who can work out what was happening?
So... if you are happy to go with float switch instead of the auto water sensor you can simply put a float switch in front of the auto supply so that both the float and the water sensor need to go on to pump...?
It only takes water droplets across the electronic sensor to make a circuit and switch the pump on. I get condensation in the bilge of my hard boat sometimes (covered boat - small amount of water in bottom (2 cups full) - heated by cover. 100% humidity I'd guess then cools down, and the humid air touches the cold sides and condenses. That dribbling down the sensor switch will be enough to switch it on.
Remember that the reason these sensors were developed was to stop debris floating into the float switch and either jamming it open (and on) or stopping it opening. If you can address the stopping opening (positioning) the jammed open will still need the electronic sensor to activate as well...