543-017

This premium 3-inch high limit switch is an essential safety component for residential and commercial forced-air heating systems. Designed to monitor internal temperatures within the furnace heat exchanger, this L180-30F control switch acts as a critical fail-safe by automatically interrupting the heating cycle if the unit exceeds safe operating temperatures. Engineered for reliability, the switch features a normally closed circuit that opens at 180 degrees Fahrenheit and resets once the temperature drops by 30 degrees. Replacing a faulty limit sensor is vital for preventing equipment damage and ensuring the safe, efficient operation of your HVAC system. This durable temperature-sensing probe is a standard requirement for maintaining optimal airflow safety and protecting against overheating in modern gas and electric furnaces.
Type: High Limit Control Switch
Size: 3-inch insertion depth
Dimensions: 3 inches
Application: Used as a primary safety thermal cutout in gas furnaces, electric furnaces, and HVAC air handlers to prevent heat exchanger overheating.
Specifications: Temperature Rating: Opens at 180°F, Closes at 150°F (30°F Differential); Circuitry: Normally Closed (NC); Mounting: Flange mount with 3-inch probe insertion.