Lennox 27H87 Limit Switch

The Lennox 27H87 Limit Switch is a critical OEM safety component engineered for precise thermal management in high-performance heating systems. This 120-160F auto limit switch is specifically designed to monitor furnace plenum temperatures, providing a fail-safe against overheating by interrupting the burner circuit if thresholds exceed the factory-calibrated 160°F limit. As a veteran-grade HVAC replacement part, the 27H87 ensures seamless integration with Lennox air handlers and furnaces, maintaining system integrity and operational efficiency for high-demand contractors. This unit is a direct 1:1 replacement, as the Lennox 27H87 is identical to 27H8701, offering the same automatic reset limit switch functionality required for modern HVACR diagnostic protocols. When troubleshooting Lennox furnace error code 201 or instances of short-cycling, replacing a fatigued or non-conductive limit control is essential to restore the correct sequence of operation and protect the heat exchanger from thermal stress.

• Precise Thermal Calibration: Factory-set to open at 160°F and close at 120°F to ensure tight safety tolerances.
• OEM Compatibility: Genuine Lennox 27H87 ensures electrical and mounting compatibility with residential and commercial units.
• Automatic Reset Logic: Eliminates manual intervention by automatically restoring the circuit once temperatures return to a safe 120°F.
• High-Durability Construction: Built to withstand the constant thermal cycling of a primary furnace limit.

• Is the 27H87 interchangeable with the 27H8701? Yes, the Lennox 27H87 and 27H8701 are functionally and physically identical components.
• What are the symptoms of a failing furnace limit switch? Common indicators include the furnace shutting down prematurely (short-cycling), the blower motor running continuously while the burners stay off, or the system triggering a high-limit fault code.
• Why does my limit switch keep tripping? While a failing switch is possible, frequently tripping is often caused by restricted airflow from dirty filters, blocked returns, or a malfunctioning blower motor.

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.