Could you go with a light-activated switch to trigger the door operation
at the change of light...like a deer feeder?

Jim

wrote:
I'm using a small pond pump (L G Sourcing Model MD 170) to operate a
contraption I built to open and close a small sliding wooden door on a
chicken coop on a timer. It pumps water into a jug that has a slow leak
so the door stays open while the pump runs all day (jug stays full),
and then at night (pump off) the water leaves the jug and the door
closes. Worked like a charm since June when I made it, but now that
cold weather is approaching, I need to modify the system. Here's my
question: Does anyone know whether or not this (or any pond pump) will
be damaged if I substitute windshield washer fluid (methanol based) for
the water?

Thanks

Lynn Willis