Reznor 205442 Pressure Switch

The Reznor 205442 Pressure Switch is a high-precision HVAC safety control designed to verify proper combustion air and draft conditions before allowing ignition. Calibrated at .20" WC (water column) with a Single Pole Single Throw (SPST) configuration, this white label pressure switch is a critical OEM replacement part for maintaining the operational integrity of commercial gas-fired unit heaters and Reznor HVAC systems. Featuring dual 1/4" barb connections for quick pneumatic hose attachment, this switch monitors the pressure differential generated by the draft inducer motor, ensuring that the system shuts down if venting is obstructed or airflow is inadequate. For veteran technicians, this 0.20 PF pressure switch offers a robust, drop-in solution to resolve intermittent furnace lockouts and pressure switch stuck open error codes on compatible gas unit heaters.

• OEM Precision: Factory-calibrated at .20" WC to match original equipment specifications for reliable safety circuit proving.
• Industrial Durability: Robust construction engineered to withstand the thermal cycling and high-demand environments typical of commercial heating systems.
• Direct Compatibility: Features the standard SPST design and dual 1/4 inch barb connections for seamless integration with existing venter housing lines.
• Operational Safety: Prevents hazardous operation by ensuring positive or negative pressure thresholds are met before the gas valve is energized.

How do I troubleshoot a Reznor 205442 that won't close?
First, verify that the inducer motor is reaching full RPM and the vent pipe is free of obstructions. Use a manometer to confirm the system is pulling at least .20" WC. If the pressure is sufficient but the multimeter shows no continuity across the SPST terminals, the switch diaphragm may be ruptured.

Can I use this switch for high-elevation applications?
Specific high-elevation kits are often required for installations above 2,000 feet. While the 205442 is standard for many models, always verify the sea level rating against your specific unit heater nameplate to ensure the set point matches the local atmospheric pressure requirements.

What are the signs of a failing pressure switch?
Typical symptoms include the inducer running indefinitely without ignitor activation, specific LED flash codes on the integrated control board, or the unit short cycling due to a fluttering contact under load.

This item is not eligible for free shipping.

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.