Carrier HH12HC171 Limit Switch

Repair high-limit error codes and restore furnace safety with the Carrier HH12HC171 Limit Switch. This OEM temperature actuated switch is a critical safety component designed to monitor heat exchanger temperatures and prevent hazardous overheating conditions. Engineered for professional HVAC applications, the Carrier HH12HC171 features a precise Open 170°F / Close 130°F configuration, ensuring the burner circuit is interrupted if internal temperatures exceed safe operating parameters.

As a SPDT auto-reset switch, it automatically resumes operation once the system cools to 130°F, provided the underlying airflow issue is resolved. This HVAC high limit replacement is essential for technicians addressing 33 code errors or unit short-cycling. Its robust construction and 240V rating make it the standard for Carrier furnace parts in residential and light industrial heating systems. Ensure maximum system durability by utilizing this direct-fit safety limit switch to maintain factory-specified thermal protection.

• Precise Thermal Control: Factory-calibrated to open at 170°F and close at 130°F for reliable equipment protection.
• OEM Compatibility: Designed specifically for Carrier, Bryant, and Payne heating units to ensure correct mounting and terminal alignment.
• Automatic Reset: Facilitates standard system recovery without manual intervention after the unit reaches a safe 130°F.
• Durable Electrical Design: Rated for up to 240V and 3.6 Amps, providing a high-performance electrical break for burner circuits.

What causes a Carrier limit switch to open prematurely?
The most frequent causes are restricted airflow due to dirty air filters, a malfunctioning blower motor, or blocked return air registers. If the switch opens at 170°F, verify static pressure and filter cleanliness.

Is the HH12HC171 a manual or auto-reset switch?
This is an auto-reset limit switch. It will close the circuit once the temperature drops below the 130°F threshold. If the system continues to trip, it indicates a persistent thermal or airflow issue rather than a switch failure.

How do I verify if the limit switch is faulty?
Test for continuity across the terminals when the furnace is cool. If you have no continuity while the switch is below 130°F, the internal bimetal disc or contacts have likely failed and require replacement.

This item is not eligible for free shipping.

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.