What To Do If You Don't Have The C Wire For Your Thermosat

What To Do If You Don't Have The C Wire For Your Thermosat

Most communicating or automation thermostats require power from the furnace in order to operate - particularly WIFI thermostats.  This power is brought up to the thermostat using the 'C' wire.  If you don't have a C wire connection, you have 4 choices:

 

  1. Run an extra wire using thermostat wire
  2. Buy a 24VAC plug-in transformer and power the thermostat locally.  You can run the wire up the wall to hide it. (see video instructions)
  3. If you have 4 or 5 wires but no C Wire, you may be able to use a Venstar Venstar thermostat add-a-wire device (see video instructions)
  4. Move over the G Wire to the C wire at the furnace and thermostat (gas/propane only - see video instructions)

 

USING A PLUG-IN POWER SUPPLY TO POWER THE THERMOSTAT

 

USE VENSTAR ADD-A-WIRE

 

STEALING THE G WIRE TO MAKE IT A C WIRE

 

 

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