Lennox 82M33 Pressure Switch

The Lennox 82M33 Pressure Switch is a critical safety component designed for precise combustion air monitoring in high-efficiency furnaces and HVAC systems. As a Single Pole Single Throw (SPST) switch with a fixed setpoint of 1.25" WC (Water Column), it ensures the inducer motor is moving sufficient air before the ignition sequence begins. This OEM Lennox replacement part features dual 1/4" barb connections, allowing for straightforward integration into the pneumatic tubing circuit of your cabinet. Built for industrial-grade durability, the Lennox 82M33 helps technicians resolve pressure switch open faults and diagnostic error codes related to venting issues or inducer failure. This part is engineered to maintain system integrity under demanding cycling conditions, ensuring the furnace pressure switch operates within narrow technical tolerances to prevent hazardous exhaust buildup or delayed ignition.

• Precise Calibration: Factory-set at 1.25" WC to match Lennox-specific static pressure requirements for optimal combustion safety.
• Secure Pneumatic Sealing: Equipped with dual 1/4" barb connections to prevent air leaks and ensure accurate vacuum readings from the inducer housing.
• Direct OEM Fit: Designed as a drop-in HVAC pressure switch for Lennox models like the CMPA075U3, reducing field modification time.
• Rugged SPST Design: Provides reliable electrical continuity in the safety loop, capable of withstanding high-cycle industrial and residential environments.

How do I troubleshoot a Lennox 82M33 fault?
Technicians should first verify that the 1.25" WC setpoint is being met by checking the inducer draft with a manometer. Inspect the 1/4" barb connections and tubing for cracks, moisture, or blockages that could prevent the diaphragm from closing the SPST circuit.

Can this pressure switch be used in other furnace brands?
While the 82M33 is a standard SPST switch, it is specifically calibrated for Lennox combustion air requirements. Using a switch with an incorrect water column rating can lead to intermittent tripping or unsafe furnace operation.

What are the signs of a failing pressure switch?
Common indicators include the inducer motor running without ignition, diagnostic LED codes for "Pressure Switch Open," or visible cracks in the housing that lead to pneumatic pressure loss.

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.