Thermostat Wiring For Furnace And Ac

The yellow wires underneath your thermostat connect to your compressor.

Thermostat wiring for furnace and ac.

That will power the relay contactor or complete the circuit in the circuit board. They control your air conditioning system. Red wire for air conditioner control power hot 1 the r terminal is the 24 volt hot feed from the control step down transformer. The transformer steps down 120 volts to the 24 volts the thermostat needs and sends out the 24 volts on two wires.

The yellow wires terminate at your compressor contactor via an air handler. Turn off your existing thermostat. Furnace 24 volt transformer. The thermostat is likely a digital thermostat that requires the c wire or the common wire to provide power for the thermostat.

C terminal to the blue wire. Y terminal to the yellow wire. Once your c wire is ready follow these steps to install your new thermostat. The two 24 volt wires go to the r terminal and c terminal inside the thermostat.

Sometimes depending on the thermostat and the manufacturer the thermostat can be a dual heat pump thermostat. Or it can be used for an air conditioner and gas furnace system depending on how the thermostat is wired. The white wire underneath your thermostat connects to your heating system. W terminal to the white wire.

Always refer to your thermostat or equipment installation guides to verify proper wiring. A thermostat with five wires typically controls an air conditioner with a heating system. The heating system will likely be a gas or electric furnace. The yellow wires connect to the y terminals on your thermostat.

R terminal for the red wire. Additionally it will require a different thermostat and different wiring than an air conditioner. It terminates at your air handler or furnace. Breakdown of colors and terminals thermostat wiring diagram for ac unit.

Notesome ac systems will have a blue wire with a pink stripe in place of the yellow or y wire. Label where the wires are connected on the thermostat. G terminal to the green wire. Flip the furnace ac breaker to the off position.

Check to see if they match the industry standard listed above. The white wire connects to terminal w in industry standard thermostats. This function allows you to circulate the air in the house by using the fan in the furnace without heating or cooling the air moving through the system.