My Honeywell TrueZone 311 board does not have a terminal for the blue wire. Where does it go? I plugged in the wires for the dampers and the thermostats, but the five wires from the furnace to the zone board are incomplete due to the lack of a c terminal.


According to the install instructions, the zone board has dedicated R and C power terminals which should be connected to the corresponding transformer wires from the furnace, or to a dedicated 24VAC transformer if the furnace's transformer is not being used. If your furnace doesn't provide a C wire (typically blue), update your post with pictures of the setup and we can provide more help.

  • for the equipment section of the zone board, I would only be using the yellow, white, green wires?
    – user60061
    Sep 14 '16 at 2:33
  • @user60061 -- R, W, Y, and G -- the R wire can be connected to the same incoming wire as the board-power R terminal is. Sep 14 '16 at 3:03

The blue wire is typically the C or common. The thermostat and zone board does not need one to operate, but without it the thermostat will run on battery power.

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