543-052

This 3-inch High Limit Switch (L190-220F) is a vital safety component designed for residential furnaces and HVAC heating systems. Functioning as a thermal protection device, this limit control monitors the heat exchanger or plenum temperature to prevent the appliance from overheating. If internal temperatures reach the designated safety threshold—specifically the 220°F limit—the switch automatically interrupts the circuit to the burner or heating element. Once the system cools to the 190°F reset point, it allows the unit to resume operation. This high-quality replacement part features a 3-inch insertion probe for precise temperature sensing, ensuring your heating system operates safely and efficiently. It is a common fix for furnaces that are short-cycling or shutting down prematurely due to airflow or temperature issues.
Type: High Limit Control Switch
Size: 3-inch insertion depth
Dimensions: 3 in
Application: Used in gas furnaces, electric heaters, and central HVAC units as a primary thermal safety cutoff.
Specifications: Temperature Range: L190-220F (Opens at 220°F, Resets at 190°F); Circuit: Normally Closed (NC); Probe Length: 3 inches.