Carrier HH18HA496 Limit Switch

For veteran contractors looking for a direct OEM replacement part, the Carrier HH18HA496 is a mission-critical safety component designed for Carrier, Bryant, and Payne gas furnaces. This furnace limit switch functions as a high-limit thermal protector, monitoring the internal temperature to prevent equipment damage. It features a specified cut-out temperature of 200°F and a cut-in temperature of 160°F. As an automatic reset limit switch, it restores the electrical circuit once temperatures return to a safe operating range, unlike manual reset rollout switches that require on-site intervention. This disc-style limit switch is engineered to meet exact OEM specifications, ensuring seamless HVAC compatibility and reliable performance in high-cycle environments. Whether you are troubleshooting a 3-flash code or resolving a blower that won’t stop running, this genuine HVAC replacement part (often cross-referenced as L200F-40 or HH18HA496A) provides the precise thermal response needed to protect the heat exchanger from overheating during restricted airflow conditions.

• Precise Thermal Control: Features a fixed 160-200°F operating range to provide reliable overheat protection and system safety.
• OEM Compatibility: A genuine Carrier HH18HA496 component that fits a wide range of PG8JAA and PG8MAA series furnace models.
• Automatic Operations: The auto reset functionality ensures the system resumes normal operation without manual resets after a temporary thermal event.
• Simplified Installation: Compact disc design with standard 1/4-inch terminals for a direct HVAC limit switch replacement in tight blower compartments.

• How do I test a Carrier furnace limit switch with a multimeter? Set your meter to continuity; a functional HH18HA496 should show a closed circuit (continuity) at room temperature and open only when reaching the 200°F trip point.
• What causes a high limit switch to trip repeatedly? Frequent tripping is usually a symptom of airflow issues, such as a clogged 1-inch pleated filter, a failing blower motor, or restricted return air ducts rather than a faulty switch.
• Can I bypass this switch for testing? While a temporary jumper can diagnose a failed switch, never leave a furnace safety switch bypassed, as it poses a severe fire hazard and risks cracking the heat exchanger.

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.