Reznor 205443 Pressure Switch

The Reznor 205443 Pressure Switch is a critical safety and operational component designed for precise 0.75" wc (water column) monitoring in high-efficiency heating systems. As a Single Pole Single Throw (SPST) switch, it provides a reliable normally open circuit that closes upon reaching the specified set point to prove draft and authorize the ignition sequence. This OEM Reznor replacement part features dual 1/4" barb connections, ensuring a secure airtight seal for pressure sensing tubes. Engineered for durability in demanding HVAC combustion blower assemblies, this switch prevents unsafe furnace operation by detecting venting obstructions or inducer motor failure. Whether you are performing routine maintenance or troubleshooting a lockout, this low pressure switch ensures your unit heater maintains peak combustion efficiency and meets strict safety protocols.

Key Benefits for Field Technicians:

• Precise 0.75" wc Set Point: Factory-calibrated for accurate pressure detection, reducing nuisances and ensuring proper draft proofing.
• Standard SPST Configuration: Simplifies troubleshooting and ensures compatibility with standard 24V control circuits found in Reznor unit heaters.
• Dual 1/4" Barb Ports: Allows for versatile pneumatic tubing configurations, providing a tight friction fit that resists vibration-induced leaks.
• Industrial-Grade Diaphragm: Built to withstand the thermal cycling and corrosive flue gases common in gas-fired heating environments.
• OEM Compatibility: Exact replacement for Reznor 205443, eliminating the need for field modifications or bracket adjustments during installation.

Common Questions:

How do I troubleshoot a 205443 switch that won't close?
Verify the inducer motor is reaching full RPM and check for blockages in the heat exchanger or venting. Use a manometer to confirm the system is pulling at least 0.75" wc at the 1/4" barb connection before concluding the switch is faulty.

Can this switch be used in positive or negative pressure applications?
Yes, the dual port design of the Reznor 205443 allows it to monitor differential pressure, making it suitable for both suction (negative) and discharge (positive) sensing depending on the tubing configuration.

What causes these switches to fail prematurely?
Most failures result from moisture or debris entering the SPST housing through the sensing lines. Ensure that any condensate traps in the pressure tubing are clear to prevent water from reaching the internal diaphragm.

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.