In applications where additional wiring cannot be run, the Add-A-Wire accessory can be used to add a wire to the thermostat. C-Wire Terminal is required
Great for installations with a broken “common” wire or retrofits.
Easy to install, Easier than running new wire.
Allows 5 wire thermostats to use only 4 wires. Also allows 5 wires to work like 6 wires.
Compatible with any 24VAC thermostat signal wiring.