Home A C Thermostat Wiring Diagram

Green the green wire connects to the fan.

Home a c thermostat wiring diagram. If you are building a new home or having your furnace replaced and re wiring you should use the 9 wire thermostat wire like this. Ac service tech llc 90 405 views. Nest forums and hvac forums seem to be full of people reporting a lack of a c wire in their home. Anecdotally my 1977 home on the west coast has a programmable thermostat but no c wire.

The thermostat is the control device that provides a simple user interface with the internal workings of your homes climate control system. Heat pumps are different than air conditioners because a heat pump uses the process of refrigeration to heat and cool while an air conditioner uses the process of refrigeration to only cool the central air conditioner will usually be paired with a gas furnace an electric furnace or some other method of heating. Blue this is your common or c wire. Again referring to the honeywell thermostat ct31a1003 wiring diagram you can see it requires only two wires r and w.

Thermostat wiring diagrams for heat pumps heat pump thermostat wire diagrams. One is for cool and the other is for heat hence the abbreviation rh and rc. Color of wire and termination. A large majority of homes today have an hvac system containing a furnace oil gas or electric and an a c unit.

Red now there can be two separate wires for this. It is a red wire and comes from the transformer usually located in the air handler for split systems but you may find the transformer in the condensing unit. The common wire sometimes referred to as the c wire is what s responsible for delivering constant power to your thermostat. It doesn t control cooling and because it s a mechanical thermostat it doesn t need power for internal functions so it has no c wire.

Orange this wire connects to your heat pump if you have one. Color code how it works diagram. With all that in mind i m guessing the c wire is in less than 20 of u s. Https amzn to 2mtzw7q doing so will ensure future compatibility.

The thermostat wiring on these systems can have very similar wiring properties. My sister s 1983 home in the midwest is also c wire less. By the use of an adjustable set point the job of the thermostat is to turn on either the heating or cooling system to maintain the desired room temperature in the home and to turn off the system when the desired temperature is achieved. For programmable thermostats and smart thermostats c wires are essential for setting a schedule or having your heat or air conditioner turn on at a desired temperature while some units can run without a c wire even brands like nest recommend having one for optimal.

How to wire a thermostat. R the r terminal is the power.