York S1-025-31926-000 Limit Switch

The York S1-025-31926-000 Limit Switch is a critical safety component designed for precise thermal monitoring in high-output HVAC systems. This SPST furnace limit switch features fixed setpoints with an open temperature of 240°F and a close temperature of 155°F, ensuring reliable high-limit protection for the heat exchanger. As a genuine York replacement part, it maintains system integrity by preventing overheating conditions that can lead to catastrophic component failure. This L240-85F thermal switch is engineered for a snap-action response, providing consistent cycling and professional-grade performance in residential and light commercial furnaces. For technicians troubleshooting HVAC limit circuit issues, this OEM component ensures exact mechanical alignment and electrical compatibility within the control string. Proper installation of this internal high limit switch is essential for maintaining the safety sequence of operation and protecting the primary heat exchanger from excessive thermal stress.

Key Technical Benefits

• Precise Thermal Calibration: Fixed 240°F trip point ensures rapid circuit interruption during over-temperature events.
• OEM Compatibility: Exact drop-in replacement for York, Luxaire, and Coleman equipment, eliminating field modification needs.
• Snap-Action Reliability: High-grade SPST contact design prevents arcing and ensures a clean break in the 24V or 120V control circuit.
• Automatic Reset: Resets at 155°F to allow the system to resume normal operation once safe temperatures are restored.
• Durable Construction: Built to withstand the high-static environments typical of modern high-efficiency blowers and burners.

Common Questions

What causes a York furnace limit switch to trip repeatedly?
Frequent tripping usually indicates restricted airflow due to a dirty filter, blocked return air, a failing blower motor, or an oversized burner orifice. If the switch stays open despite normal airflow, the internal bimetal disc may have lost its calibration.

Can I bypass the S1-025-31926-000 for testing?
Temporary bypassing is only for immediate diagnostic continuity checks by a qualified technician. Operating a furnace with a bypassed high limit safety switch is extremely hazardous and can result in heat exchanger damage or fire.

Is this switch compatible with other HVAC brands?
While designed as a York OEM part, it can be used in other systems requiring an L240-85F limit switch with the same mounting footprint and electrical ratings. Always verify the specific temperature rise of the equipment before substitution.

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.