I use a windshield wiper delay switch to operate a DC water pump to circulate water through my collector panels to my hot water heater. I control it by leaving the wiper switch on with an interval of 22 seconds off and 2 seconds on. To determine time of day the pump will operate I installed an AC lamp timer set to operating times connected to an AC/DC D.P.D.T. relay which I routed the windshield wiper DC power lines through. The output from the windshield wiper delay switch is then routed through a standard auto 30W S.P.S.T relay so a separate dedicated circuit will provide power to the DC pump. My 12VDC pump sprung a leak and I didn’t want to take cold showers. So, I had a small AC pump that could be used to circulate the water already on hand. I spliced AC pumps the black lead wire and connected one lead to the red relay wire and the other to the yellow relay wire of the auto relay. The blue relay wire connected to the wiper delay switch operates the relay when the green wire is connected to ground. Plugged the AC pump into a wall outlet. The result was it works just fine until I can replace the DC pump. Note: The standard auto relay mentioned comes with one additional orange wire, which is for ignition and is not used. Changeyourlatitude