In article ,
"Michael Kennedy" wrote:

Does anyone know where to get a water flow meter that will close or open a
switch when water is flowing? I have an AC unit that uses water to cool
itself and it produces 110 deg water if you reduce the flow enough. I'm
trying to build a setup that will switch between the on demand hot water
heater and the AC unit for the house. The major difficulty is determining if
there is water flow to the hot water lines in the hosue..

Thanks,

Mike

Jacuzzi heater safety switch is a NO switch that closes when water flows
(i.e. pump is on and working.)