What is a contactor?
Be definition, it’s a device for making and breaking an electric circuit. In simpler terms, a contactor is a switch for switching power.
What does it do in an air conditioning system?
Its purpose is to send volts to the air conditioning condenser or heat pump. crankcase heater, and fan motor. The contactor works hand-in-hand with the thermostat. When the thermostat requests power, it “pulls” volts from one side of the contactor, which is always powered, to the other. When the thermostat doesn’t need anymore, it opens and stops all power to the equipment. In other words, it powers up the unit with the help of a thermostat.