Thermostat Wiring For Furnace And Ac

It terminates at your air handler or furnace.

Thermostat wiring for furnace and ac.

They control your air conditioning system. The yellow wires connect to the y terminals on your thermostat. Furnace 24 volt transformer. Thermostats use 24 volts ac from a transformer to control a furnace.

G terminal to the green wire. W terminal to the white wire. R terminal for the red wire. Red wire for air conditioner control power hot 1 the r terminal is the 24 volt hot feed from the control step down transformer.

Turn off your existing 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. Once your c wire is ready follow these steps to install your new thermostat.

Flip the furnace ac breaker to the off position. The white wire underneath your thermostat connects to your heating system. Additionally it will require a different thermostat and different wiring than an air conditioner. A thermostat with five wires typically controls an air conditioner with a heating system.

Breakdown of colors and terminals thermostat wiring diagram for ac unit. This diagram is to be used as reference for the low voltage control wiring of your heating and ac system. Y terminal to the yellow wire. The yellow wires terminate at your compressor contactor via an air handler.

The white wire connects to terminal w in industry standard thermostats. The thermostat is likely a digital thermostat that requires the c wire or the common wire to provide power for the thermostat. That will power the relay contactor or complete the circuit in the circuit board. Check to see if they match the industry standard listed above.

Notesome ac systems will have a blue wire with a pink stripe in place of the yellow or y wire. The heating system will likely be a gas or electric furnace. The two 24 volt wires go to the r terminal and c terminal inside the thermostat. Label where the wires are connected on the thermostat.

In the most basic system this functionality is provided by use of a fan center relay and the low voltage wiring to the thermostat now will require a minimum of three wires for heat only. Always refer to your thermostat or equipment installation guides to verify proper wiring. C terminal to the blue wire.