543-170

This premium 3-inch high limit switch is a vital safety component designed for residential gas furnaces and HVAC heating systems. Functioning as a thermal cutout, this switch monitors the temperature within the heat exchanger to provide essential overheating protection. When the internal air temperature reaches a critical threshold of 170°F, the switch automatically interrupts power to the heating element or burner, preventing equipment damage and ensuring home safety. This reliable replacement part features an automatic reset with a 40°F differential, meaning it will restore system operation once temperatures have cooled to a safe level. Engineered for durability and precision, this furnace limit control is a common solution for systems experiencing cycling issues or safety shutdowns.
Type: High Limit Control Switch
Size: 3-inch insertion length
Application: Used in forced-air gas furnaces and HVAC heating units as a primary safety sensor to prevent overheating and equipment failure.
Specifications: Temperature Cut-out: 170°F; Temperature Differential: 40°F; Reset Type: Automatic; Mounting Style: Flange mount with 3-inch probe depth.