York S1-025-43257-000 Gas Valve

Optimizing high-efficiency burner performance requires the precision of the York S1-025-43257-000 Gas Valve. As a primary OEM modulating gas valve, this Gen 2 component is engineered for 97% AFUE multi-position furnaces, providing seamless gas flow regulation to eliminate temperature swings. Unlike standard single-stage models, this 3/4-inch NPT gas valve utilizes a 24V control signal to modulate output between 0.42" and 3.5" WC, ensuring the manifold pressure precisely matches the heating demand. This White-Rodgers 36J27-508 equivalent features a rotary dip switch for field adjustments and supports both Hot Surface Ignition (HSI) and Direct Spark Ignition (DSI) systems. Designed for reliability in dense mechanical cabinets, it handles an ambient temperature range of -40°F to 175°F. For contractors servicing York, Coleman, or Luxaire equipment, this modulating furnace valve is a drop-in replacement that restores factory-spec combustion efficiency and improves blower-to-fire synchronization in complex modulating cycles.

• Precise Modulation: Regulates gas delivery between 0.42" and 3.5" WC for consistent discharge air temperatures.
• OEM Compatibility: Authentic S1-025-43257-000 replacement ensures proper fitment in 97% modulating York furnace cabinets.
• Versatile Ignition Support: Fully compatible with both HSI and DSI ignition sequences for broad application across Gen 2 platforms.
• High-Efficiency Integration: Specifically tuned for modulating HVAC systems to maintain optimal fuel-to-air ratios.
• Simplified Field Setup: Features a rotary dip switch for streamlined pressure regulation and manifold calibration.

• Can this valve be used for LP conversions? Yes, although it is pre-calibrated for natural gas, it supports LP gas through a compatible conversion kit (sold separately).
• Does this replace the older Gen 1 valves? This is a Gen 2 modulating gas valve; always verify the furnace control board software version to ensure communication compatibility.
• What are the port sizes? This unit features standard 3/4" NPT inlet and outlet connections for high-capacity flow.

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.