Thermostat Wiring Heat Pump Gas Furnace

For example if the red wire is connected to w on the thermostat the furnace should turn on.

Thermostat wiring heat pump gas furnace.

Furnace thermostat wiring diagram terminal letters on a thermostat and what they control the hot wire 24 volts usually red from the transformer is the main power wire to turn on or off a furnace components. See the diagram below for what each wire controls on your system. Therefore you will use the following color code for simple thermostat wiring. Before uninstalling the old thermostat take a picture of the wiring with your cell phone before removing the wires.

Heating only thermostat wiring diagrams if you only have a furnace such as a gas furnace oil furnace electric furnace or a boiler. The basic heat pump wiring for a heat pump thermostat is illustrated here. Terminal r or terminal rh for the red wire. The thermostat uses 1 wire to control each of your hvac system s primary functions such as heating cooling fan etc.

When the red wire is disconnected from w the furnace should turn off. This originates from the transformer. Both the furnace control board and the thermostat will usually have the same terminal letters. This way you have a reference.

It corresponds to the chart below to explain the thermostat terminal functions.