Carrier HH18HA187 Limit Switch

The Carrier HH18HA187 Limit Switch is a critical OEM replacement part designed for high-limit safety monitoring in residential and commercial gas furnaces. This SPST normally closed disc-style switch features a fixed 180-degree open setpoint and a 80-degree close reset point, ensuring the heat exchanger does not exceed safe operating temperatures. Engineered for automatic reset functionality, the HH18HA187 integrates seamlessly into the safety string of Carrier, Bryant, and Payne equipment, providing reliable protection against rollout and overheating conditions. With a robust contact rating of 26A at 120VAC, this HVAC limit switch is built to handle the inductive loads of modern blower motors and control boards, maintaining system integrity even in demanding duty cycles. Replacing a fouled or tripped limit switch with this factory-authorized component restores the original manufacturer's specifications for thermal protection.

• Precise Thermal Protection: Factory-calibrated to open at 180°F and reset at 80°F (L180-100F) for exact furnace safety switch performance.
• Direct OEM Fit: Designed as a drop-in replacement for the Carrier HH18HA187A, eliminating the need for mounting modifications.
• High Electrical Capacity: Rated for 26 Amps at 120V and 13 Amps at 240V, ensuring durability under high current draw.
• Automatic Reset Logic: The automatic limit switch design restores the circuit once temperatures return to the 80°F safe zone, reducing unnecessary downtime.

What causes a Carrier HH18HA187 to trip?
A tripped limit switch usually indicates restricted airflow due to a dirty filter, a failing blower motor, or an undersized duct system causing the heat exchanger to overheat.

Is the HH18HA187 compatible with multiple brands?
Yes, as a factory authorized part, it is the standard 180-degree limit for many Carrier, Bryant, and Payne furnace models.

How can I verify if my furnace needs this specific switch?
Check the stamping on your existing disc; if it specifies an L180-100 or matches the HH18HA187 part number, this is the correct technical replacement.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.