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What To Do If You Don't Have a C Wire For Your Thermostat

HeatingHelp Administrator Posts: 653
edited February 2023 in THE MAIN WALL

The common wire is the neutral wire from the 24V transformer that provides the power that WiFi thermostats require in order for their features to work. Most existing homes do not have a C wire since non-connected thermostats don’t require them.

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  • Shawny416
    Shawny416 Member Posts: 1
    You can simply install a plug in 24 volt transformer and run the tiny wires to your thermostat externally. I have done this many times over the years for these wifi thermostats and it has worked out fine with no problems!
  • NEMatt
    NEMatt Member Posts: 56
    Pull a new cable with more than two conductors.  FastStat Common Maker works too.
  • unclejohn
    unclejohn Member Posts: 1,833
    Put in Batteries