543-502

This 3-inch fixed high limit control switch is a critical safety component designed for HVAC systems and forced-air furnaces. Engineered to monitor internal temperatures, this thermal limit switch prevents equipment overheating by automatically breaking the electrical circuit when the temperature reaches 120°F. The built-in auto-reset feature ensures the switch closes again once the system cools down by 30°F, allowing for seamless operation without manual resetting. This durable replacement part is essential for maintaining the safety and efficiency of residential and commercial heating units, providing reliable thermal protection against restricted airflow or blower failure.
Type: High Limit Control Switch
Size: 3-inch probe depth
Dimensions: 3 in
Application: Used as a safety cutout in furnaces, heaters, and HVAC air handling units to prevent heat exchanger damage and ensure safe operating temperatures.
Specifications: Fixed temperature setting: Opens at 120°F; 30°F differential (Resets at 90°F); Automatic reset functionality; 3-inch insertion probe.