Wiring Diagram Thermostat Honeywell. The model number of the honeywell thermostat was not provided however here are the typical wiring assignments for a conventional heating system. Keep in mind that there should be a low voltage cable in the wall where the thermostat is located which has individual wires as shown in the instructions below. On the other hand the diagram is a simplified version of this arrangement.
If you have a trane model thermostat and have a wire labeled x or b refer to your thermostat manual. On the other hand the diagram is a simplified version of this arrangement. But here is a list of the most common wire color mappings as seen in many four wire t stat setups. The thermostat makes a contact on both a rise and on a fall of room temperature.
If you check the honeywell thermostat ct31a1003 wiring diagram you ll see that it requires only two wires.
C 24 vac common you might see blue purple or brown typically used for this wire. This makes the process of assembling circuit simpler. If you have a c wire place it into the c terminal on your wall plate. Keep in mind that there should be a low voltage cable in the wall where the thermostat is located which has individual wires as shown in the instructions below. At left the thermostat wiring diagram illustrates use of a honeywell t87f thermostat in a 3 wire application as a spdt single pole double throw switch such as used to control low voltage motors electric radiator valves zone valves.