York S1-025-41318-000 Limit Switch

The York S1-025-41318-000 Limit Switch is a critical safety component designed for precise thermal monitoring in high-output furnace applications. This mechanical reset limit switch is calibrated to trip at 250°F, effectively preventing heat exchanger damage and ensuring the unit operates within safe thermal parameters. Engineered for York residential heating systems, this SPST (Single Pole Single Throw) switch opens on temperature rise, providing a hard break in the safety circuit when internal plenum temperatures exceed the factory-defined threshold. The manual reset (M/R) configuration requires a technician to physically inspect the system for airflow obstructions or combustion issues before restoring operation, which is vital for preventing recurring overheating cycles.

When performing a furnace limit switch replacement, the S1-025-41318-000 offers a drop-in fit for specific Coleman, Luxaire, and York air handlers and furnaces. The L250-F manual reset functionality is essential for maintaining UL safety compliance in HVAC high-limit control circuits. Contractors should verify the temperature rating and mounting orientation to ensure the probe is correctly positioned in the airstream for accurate thermal sensing. This heavy-duty York OEM replacement part ensures electrical continuity is maintained under normal load while providing reliable circuit interruption during restricted airflow or blower motor failure scenarios.

• Precise Thermal Calibration: Factory-set to 250 degrees Fahrenheit to protect the heat exchanger from structural fatigue.
• Manual Reset Safety: Prevents the system from auto-cycling in a dangerous overheat condition, forcing an inspection of the high-limit fault.
• OEM Compatibility: Direct replacement for several York S1-025 series part numbers, ensuring correct terminal alignment and mounting depth.
• Durable Construction: Built to withstand constant thermal cycling within the furnace cabinet without drifting from its set point.

Common Questions

What causes a 250F manual reset limit switch to trip?
A trip is typically caused by restricted airflow, such as a severely clogged furnace filter, a failing blower motor, or obstructed return air ducts. It can also indicate an over-fired burner or a cracked heat exchanger.

Can I replace a manual reset switch with an automatic reset switch?
No. You must always use the reset type specified by the manufacturer. A manual reset switch is a deliberate safety feature that requires a technician to diagnose the cause of the high-limit trip before the furnace can be restarted.

How do I test the York S1-025-41318-000 for continuity?
With the power disconnected and the wires removed, a multimeter should show 0 ohms (closed) across the terminals. If the circuit is open at room temperature, try depressing the manual reset button. If it remains open, the internal bi-metal disc has failed.

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.