Thermostat cables are used in the regulating of temperatures in a room or dedicated space. As HVAC thermostat wiring, these cables are typically composed of conductors, in the form of separate wires, encased in a plastic jacket. Each of the wires delivers current to a separate component or switch operated by the thermostat switch. Typically two to six components may be powered by the current coming through the cable’s wire from a 2 to 6 wire thermostat, including any or all of the following: furnace (usually a white wire), compressor (usually yellow), 24 VAC (usually red), fan (usually green), and others. Cables vary by number of conductors (encased wires), voltage, spooling, length, wire size (AWG), jacket color, compliance standards met, and other considerations. For more on HVAC thermostat wiring products, see our low voltage thermostats and wire connectors.