543-210

The 3-inch High Limit Switch L210-40F is a vital safety component designed for residential forced-air furnaces and heating systems. This thermal limit control serves as a primary safety mechanism, monitoring the air temperature within the heat exchanger to prevent dangerous overheating. If the temperature exceeds the calibrated threshold of 210°F, the switch automatically breaks the electrical circuit to the burner or heating elements, protecting the unit from damage and ensuring home safety. Once the system cools by the designated 40°F differential, the switch automatically resets to restore normal operation. This high-quality replacement part is essential for resolving issues related to furnace short-cycling or thermal cut-out failures caused by restricted airflow or mechanical malfunctions.
Type: High Limit Control Switch
Size: 3-inch insertion depth
Dimensions: 3 inches
Application: Used in gas and electric forced-air furnaces as a safety limit to monitor heat exchanger temperatures and prevent thermal overload.
Specifications: Open Temperature: 210°F; Close Temperature: 170°F (40°F Differential); Reset Type: Automatic; Configuration: Normally Closed (NC) SPST; Probe Length: 3 inches.