The LiftMaster 74-16685 Thermal Sensor Kit is an OEM replacement overheat sensor designed for select LiftMaster operators. This thermal protector monitors the operating temperature of the motor/drive assembly and opens the circuit when excessive heat is detected, helping prevent damage during heavy-duty or high-cycle use. Once the unit cools, the sensor typically resets to restore normal operation. It’s a practical repair part for troubleshooting symptoms such as unexpected shutdowns under load or frequent duty, helping maintain reliable performance in compatible LiftMaster commercial door openers and gate operators.
Use this kit when the original thermal sensor is faulty or out of calibration. Installation should be performed by a qualified technician following the model-specific LiftMaster service manual, with power disconnected and proper lockout/tagout observed. Routing and termination of the sensor leads vary by operator, so confirm the correct connection points on your control board or motor assembly and verify compatibility against the parts diagram for your exact model and series. Do not bypass thermal protection, as it is a safety component that protects the motor and supports compliant operation in residential or commercial applications.