Carrier HH12ZB260 Limit Switch a failed blower door safety

a failed blower door safety switch is often the culprit

Durable Construction: Built to withstand the high-temperature environment of the heat exchanger plenum for consistent performance

This switch mounts directly to the burner box

Frequent tripping usually indicates poor combustion air supply

Enhanced System Protection: Integrated compressor lockout logic prevents short cycling

Carrier HH12ZB260 Limit Switch a failed blower door safetyThe Carrier HH12ZB260 Limit Switch is a critical safety component engineered for precise thermal regulation in Carrier, Bryant, and Payne furnaces. This auto reset limit switch features a Normally Closed (NC) configuration, designed to break the electrical circuit when the plenum temperature reaches its 260F opening setpoint. Once the heat exchanger cools to the 220F closing temperature, the SPST (Single Pole Single Throw) switch automatically resets,