FEATURES: Can be used when a common wire is required. INSTALLATION – 1)The THP9045 Wiring Module can be equipment- or wall-mounted in any orientation or as dictated by the surroundings, 2)Precise leveling of the THP9045 module is not required. 3) Identify the four wires in the wall and connect to the R, C, W, and K terminals on the thermostat. 4) Wire the K terminal on the thermostat to the K terminal on the THP9045 module. 5) Wire the R and C terminals on the thermostat to the R (power) and C (common) terminals on the THP9045 module and equipment. 6) Wire the W terminal from the thermostat to the W (heat relay) terminal on the HVAC equipment. 7) Wire the Y and G terminals on the Module to the Y (Compressor Relay) and G (Fan Relay) terminals on the HVAC equipment. The THP9045 Wiring Module is designed to be used with applicable thermostats in which a 24V common is required and there are not enough wires. The K terminal on the thermostat can be used to operate both the fan and compressor on a single wire, and the module is designed to receive the signal from the K terminal, split that signal and re-route it to operate the compressor, and/or fan for normal operation.