York S1-025-26339-001 Limit Switch

The York S1-025-26339-001 Limit Switch is a primary safety component engineered for precise thermal monitoring in residential and light commercial forced-air systems. This 100-250F auto limit switch features an automatic reset mechanism, designed to break the 24V control circuit if the heat exchanger plenum exceeds the calibrated 250°F threshold. As a critical furnace high limit sensor, it prevents thermal stress and potential heat exchanger cracks by interrupting the gas valve operation while allowing the blower motor to dissipate residual heat. This OEM York replacement part ensures exact electrical specs and mounting footprint for seamless integration into York furnace safety controls. When troubleshooting short-cycling or "limit circuit open" fault codes, installing this factory-specified HVAC temperature limit switch restores system sequencing and protects the equipment from restricted airflow or over-firing conditions.

• Factory OEM replacement ensures correct temperature calibration and terminal orientation for York, Luxaire, and Coleman equipment.
• Automatic reset functionality simplifies system recovery once internal temperatures return to safe operating parameters.
• Broad 100°F to 250°F range provides robust protection against overheating caused by fouled filters or blower motor failure.
• Heavy-duty construction designed for high-cycle reliability in demanding heating environments.
• Direct fit mounting reduces installation time for field service technicians during emergency repairs.

What causes a York furnace limit switch to trip?
Tripping is typically caused by restricted airflow, such as a dirty air filter, blocked return vents, or a failing indoor blower motor, leading to excessive plenum temperatures.

Can I use a manual reset switch to replace this S1-025-26339-001?
No. You must maintain the original engineering logic of the system. This is an automatic reset switch; replacing it with a manual reset version can lead to improper system cycling and safety issues.

How do I verify if this limit switch is faulty?
Using a multimeter, check for continuity across the terminals when the system is cool. If the switch remains open at room temperature, the internal bimetal disc has failed and requires 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.