Six-wire thermostats are commonly seen with heating systems that have two stages of heat and one stage of air conditioning. Two stages of heat means that when the thermostat first calls for heat, the furnace will turn on using the low setting first. If the temperature is not satisfied after a certain number of minutes, the furnace will ramp up to a higher output of heat and will run at this higher setting until the temperature is satisfied. With a few tools, it is fairly easy to replace a six-wire thermostat.
Things You'll Need
- Drywall anchors
- Cordless drill
Turn off power to the furnace and air conditioner by switching the correct breakers off in the circuit breaker panel.
Remove the old thermostat from the wall by gently pulling it off the wall plate. Disconnect each thermostat wire and label it with what terminal it connected to.
Remove the old wall plate from the wall and mount the new thermostat wall plate using drywall anchors and screws.
Connect each thermostat wire to the new thermostat. Make sure they are connected to the same lettered terminal that they were connected to on the old thermostat.
Turn the power back on to the furnace and air conditioner. Set the thermostat to your desired setting.
Tips & Warnings
- Usually the red wire is connected to the "R" terminal, the white wire is connected to the "W" terminal, the green wire is connected to the "G" terminal, the yellow wire is connected to the "Y" terminal, the black wire is connected to the "C" terminal, and the brown wire is connected to the "W2" terminal on six-wire thermostat setups.
- Make sure the power is off to the furnace and air conditioner before disconnecting wires on the thermostat. Failure to do this could result in a short circuit on the furnace control board.
- High Performance HVAC: Thermostat Wiring Colors
- Timothy Gonyo; Sheet Metal Workers Local #18; Milwaukee, WI
- Photo Credit Jupiterimages/Creatas/Getty Images
How to Connect Thermostat Wiring
Putting in a digital thermostat helps control your heating and cooling bill and maintains a more even temperature throughout your home. You...
How to Wire a Honeywell Thermostat
Your programmable Honeywell thermostat can help you save up to 33% on your utility bill. It adjusts the temperature up and down...
How to Wire a Thermostat
Your common electronic programmable thermostat operates off four wires to control both the heater and the air conditioning unit. When you wire...
How to Install a Six Wire Thermostat
The number of thermostat wires varies depending on if you have a furnace, heat pump, air conditioner and how many stages each...
How to Install a Thermostat With 7 Wires
Depending on what your HVAC (heating, ventilating and air conditioning) system does, it may have two, four, five, six or seven thermostat...
How to Replace an 8 Wire Thermostat
If you've ever pulled off your thermostat, you'll notice that there are a number of wires attached to it. These wires run...
How to Replace a Honeywell 2-Wire Thermostat
Honeywell manufactures a wide range of thermostatic controls, from basic and economical to digitally programmable for more complex HVAC systems. For typical...
How to Wire an AC Thermostat in an RV
In common with most coach accessories in an RV, the thermostat that controls the air conditioner (AC) is a regular household unit....
How to Wire the Thermostat to a Comfortmaker
Comfortmaker manufactures gas and oil furnaces, heat pumps and air conditioners. It is one of seven brands of International Comfort Products Corporation....
How to Wire an RV Thermostat
Coach thermostats in recreational vehicles, or RVs, fulfill the same purpose as thermostats in regular "sticks-and-bricks" houses. They control the output of...