A heating-only thermostat is the easiest thermostat to install. It only uses two wires, usually red and white. The red wire is the power wire and the white wire is the heating wire. When the thermostat calls for heat, contacts in the thermostat close the connection between the red and white wires. This energizes power to the furnace and allows it to turn on and heat your home. When the temperature is satisfied, the contacts open and the furnace turns off.
Things You'll Need
- Drywall anchors
- Cordless drill
- Wire stripper
Make sure the power to the furnace is off. Switch the breaker to the "Off" position.
Take the thermostat wall plate and mount it to the wall. Use drywall anchors and screws to hold it tight to the wall. Check it with a level and make adjustments as necessary to ensure it is level.
Strip the ends of the red and white wires back 1/4 inch with a wire stripper. Connect the red wire to the "R" terminal and the white wire to the "W" terminal.
Push the thermostat onto the wall plate until it snaps into place.
Remove the access panel from the furnace and look for the thermostat wire. It should connect to a terminal strip on the control board. Check to see that the red wire is on the "R" terminal and the white wire is on the "W" terminal. If not, make these changes.
Put the access panel back on the furnace and turn the power back on. Set your thermostat to your desired setting.
Tips & Warnings
- The power needs to be off to the furnace when doing any low-voltage wiring. Failure to do this can result in a short circuit at the furnace along with possible electrical shock and/or electrocution.
- High Performance HVAC: Thermostat Wiring Colors
- Timothy Gonyo; Sheet Metal Workers Local #18; Milwaukee, WI
- Photo Credit Jupiterimages/Photos.com/Getty Images
How to Wire a Furnace Thermostat With 2 Wires
The simplest setup for a heating system is a thermostat that is wired with two wires. In order for a thermostat to...
How to Install a Two Wire Thermostat
Depending on the heating system you have, you can have from two all the way up to eight wires that run from...
How to Install a Wall Heater Thermostat
Replacing a wall heater thermostat is something most homeowners will need to do at one point or another. It may be because...
How to Install a Honeywell CT87K Thermostat
If you've started to notice a rise in your heating bills, uneven heating, or your heating system switching on and off more...
How to Wire a Honeywell Digital Thermostat
Honeywell manufactures digital thermostats for residential air conditioning and heat pump systems. A digital thermostat precisely measures temperature and its display screen...