Project Guide

Installing a Thermostat

1
TURN OFF POWER TO HVAC SYSTEM
Turn power off to HVAC - Installing a Thermostat
  • Begin by turning off the power for your heating and air-conditioning system at the main service panel. 
  • Remove the old thermostat cover plate with a screwdriver.
2
REMOVE OLD THERMOSTAT
Remove old thermostat - Installing a Thermostat
  • Unscrew the thermostat mounting screws and remove the thermostat body. 
  • Label the low-voltage wires to identify their screw-terminal locations using masking tape and then disconnect the wires. 
  • Remove the thermostat base by loosening the mounting screws. Tape the wires to the wall to prevent them from slipping into the wall cavity.
3
INSTALL NEW THERMOSTAT
Install new  thermostat - Installing a Thermostat
  • Thread the low-voltage wires through the base of the new thermostat and mount the thermostat base on the wall using the screws included with the thermostat. 
  • Connect the low-voltage wires to the appropriate screw terminals on the thermostat base following the installation diagram in the new thermostat's owner's manual. 
  • Optional: Locate the low-voltage transformer that powers the thermostat. The transformer is usually located near the heating and air-conditioning system or inside of a furnace access panel. Tighten any loose wire connections and make sure the wires and sheathing are in good condition. 
  • Install the battery or batteries in the thermostat body (if applicable), and attach the body to the thermostat base. 
  • Restore power to your heating/cooling system, then program the thermostat according to the manufacturer's instructions.