The Reznor 204327 SPDT Pressure Switch is a critical safety control designed for precise combustion air pressure monitoring in commercial and industrial gas-fired unit heaters. Featuring an SPDT (Single Pole Double Throw) configuration, this switch provides versatile electrical circuit control, ensuring that the ignition sequence only initiates when the proper venting draft is established. Built for high-demand HVAC environments, the Reznor 204327 is calibrated with a 0.58" WC set point, making it an essential component for maintaining burner efficiency and preventing hazardous operation under restricted airflow conditions. This genuine OEM replacement part ensures seamless compatibility with specific Reznor unit heater models, including those requiring the 116M31 or Honeywell IS20310-5473 cross-references. For service technicians, this switch offers reliable low-pressure detection and durable diaphragm performance to reduce short-cycling and diagnostic callbacks on the job site. Key Benefits for Contractors Precise 0.58" WC Calibration: Specifically engineered to match the OEM airflow specifications of Reznor heating systems for accurate safety circuit activation. SPDT Electrical Versatility: The single pole double throw design allows for flexible wiring into various furnace control boards and safety loops. Rugged Construction: Designed to withstand the thermal cycling and environmental stress typical of industrial HVAC applications. OEM Compatibility: Replaces factory parts without the need for field modifications, ensuring a perfect fit and matched inducer motor response. Common Questions & Troubleshooting What are the symptoms of a failing pressure switch? Common issues include the inducer motor running without ignition, system lockout with specific error codes, or the furnace short-cycling during a heat call. How do I verify the switch is functioning? A technician should use a manometer to measure the actual vacuum produced by the inducer blower and compare it against the 0.58" WC rating while checking for electrical continuity. Can a blocked vent cause this switch to trip? Yes, any exhaust restriction, such as debris or bird nests in the flue, will prevent the switch from closing, which is its primary safety function. 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.
