543-026

The 3-inch High Limit Switch is a vital safety component designed for HVAC systems and gas furnaces. This thermal limit control monitors the internal temperature of the furnace's heat exchanger, acting as a failsafe to prevent overheating. When the temperature exceeds the safe operating threshold, the switch opens the electrical circuit to shut down the burners, protecting the appliance from damage and ensuring home safety. This specific switch is a normally closed sensor that triggers at 180°F and features a 30°F differential for the reset cycle. It is an essential replacement part if your heating system is short-cycling, the blower fan is running constantly, or the furnace fails to stay ignited due to a tripped safety sensor.
Type: High Limit Control Switch
Size: 3-inch probe length
Dimensions: 3 inches (insertion depth)
Application: Forced-air furnaces, residential heating systems, and HVAC units requiring a fixed-temperature thermal cutout.
Specifications: Cut-out temperature: 180°F; Cut-in temperature: 150°F; Differential: 30°F; Automatic reset; 3-inch insertion probe.