This is basic heat only thermostat, with only 3 buttons on the device. Honeywell Home RCHT8610WF2006/W, T5 Smart Thermostat, Black. Attach the thermostat faceplate and turn the power back on. Learn how much a Wi-Fi Thermostat could save you on your energy bills. I HAVE ALL THE WIRING HOOKED UP PROPERLY, THE FAN WORKS BUT THE THERMOSTAT WILL NOT TURN ON THE HEAT. Thank you for your electrical wiring questions. guidelines. It is a diagram drawn to I.E.E. The common wire, sometimes referred to as the c-wire, is what’s responsible for delivering constant power to your thermostat. Tools Required: Basic Electricians Pouch Hand Tools. Sometimes even for the above common color uses, the exact purpose of a wire is often not clear. This manual thermostat's versatility is increased substantially with its implementation of a 2 or 4 wire non polarized connection.