This 1/2" bimetal disc limit switch features a fixed open temperature of 170°F and a fixed close temperature of 130°F

It is commonly used as a universal large-format guard for various 24V control brands

and 3003 series

and TH8321 VisionPRO models

This specific York temperature limit switch is typically utilized in 24V control circuits

Copeland Comfort Control (White Rodgers) 3L09-12 Limit Switch This 1/2" bimetal disc limitThe Copeland Comfort Control (White Rodgers) 3L09 12 Limit Switch is a high reliability 1 2" bimetal disc limit control engineered for precision high limit protection in residential and commercial furnaces. This board mounted HVAC limit switch features a fixed open temperature of 220F and a fixed close temperature of 180F. Operating on an open on rise switch action, it serves as a critical safety component to prevent heat exchanger damage or hazardous