York S1-024-25329-704 Pressure Switch

The York S1-024-25329-704 Pressure Switch is a critical OEM replacement part designed for precision monitoring of inducer motor performance in York, Coleman, and Luxaire furnaces. This furnace draft exhaust switch is calibrated to a 1.9" WC setpoint with a SPNO (Single-Pole Normally Open) configuration. Engineered for a close-on-fall sequence, this component ensures the vacuum pressure remains within safety parameters before allowing the ignition cycle to proceed. By establishing a reliable circuit once the correct flue vacuum is achieved, it protects the system against venting failures and inducer motor malfunctions. Built by Source 1 for Johnson Controls, this HVAC air pressure switch (MPN 024-25329-704) provides the exact form and fit required for high-efficiency residential heating units. For contractors, using this genuine component eliminates the risks associated with improper switching thresholds in venter pressure switches, maintaining the long-term reliability of the combustion safety loop.

• Precise 1.9" WC Calibration: Ensures accurate vacuum detection for safety-critical flue operation.
• SPNO Close-On-Fall Logic: Prevents furnace ignition unless the inducer motor establishes sufficient negative pressure.
• Direct OEM Compatibility: Verified fit for Source 1, York, Luxaire, and Coleman heating systems, replacing legacy part numbers and various MPL 9370DO series switches.
• Safety Integrity: Monitors for blocked vents, failed inducer motors, or improper airflow to prevent carbon monoxide hazards.

What happens if the pressure switch fails to close?
If the S1-024-25329-704 does not detect the required 1.9" WC pressure "fall," the control board will lock out the ignition sequence, usually resulting in a diagnostic code indicating a pressure switch error.

Is this switch compatible with other brands?
While primarily used in York HVAC units, this OEM furnace part is the standard replacement for many Coleman and Luxaire furnaces requiring a -1.90" WC rating.

Can I use a switch with a different WC rating?
No. Pressure switches are safety devices calibrated to specific blower and venting specs; using a different rating can lead to unsafe combustion or nuisance shutdowns.

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.