York S1-024-40873-000 Pressure Switch

The York S1-024-40873-000 Pressure Switch is a critical safety component engineered for precise airflow monitoring in modern HVAC systems. Designed with a 0.85" WC setpoint, this SPNO (Single Pole Normally Open) switch utilizes a "Close On Fall" logic to confirm the inducer motor is moving exhaust gases safely through the vent system. As a direct OEM replacement for S1-024-35786-000, it ensures factory-spec calibration and timing for sequence of operation, preventing hazardous conditions like carbon monoxide buildup or ignition failure.

For technicians in the field, this York furnace pressure switch provides the high-performance sensitivity required to eliminate erratic 3-flash error codes and short-cycling issues caused by aged or out-of-spec safety controls. Its robust internal diaphragm is built to withstand thousands of cycles while maintaining the strict .85" water column tolerance necessary for high-efficiency gas furnaces. When performing a diagnostic, always confirm the inducer is creating a vacuum exceeding the make-point of 1.00" WC to ensure reliable contact closure and trouble-free ignition.

• Direct OEM Compatibility: Specifically designed to replace York part number S1-024-35786-000 without mounting or wiring modifications.
• Precise 0.85" WC Setpoint: Delivers accurate sensing to protect the heat exchanger and maintain furnace efficiency.
• SPNO Configuration: Reliable Single Pole Normally Open design ensures the system fails-safe if pressure is lost or the inducer fails.
• Industrial-Grade Build: Engineered for durability in high-demand residential and commercial HVAC applications.

• Is this switch compatible with my specific model? This part is the verified OEM replacement for the S1-024-35786-000. Always cross-reference your specific furnace model to ensure the 0.85" WC rating matches your cabinet requirements.
• Will this fix a 3-flash error code? While a 3-flash code often signals an open furnace pressure switch, you should first check for blocked vents, cracked pressure tubing, or a failing inducer motor before replacing the switch.
• Can I use this to replace a different WC rated switch? No. Pressure switches are calibrated for specific inducer and heat exchanger combinations. Using a different setpoint can lead to safety hazards or system lockouts.

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.