Lennox 26W76 Pressure Switch

The Lennox 26W76 Pressure Switch is a critical safety component engineered for precision monitoring of inducer motor draft in residential and commercial heating cycles. This single-pole, single-throw (SPST) switch is factory-calibrated to actuate at .40" WC and reset at 0.55" WC, ensuring that the burner only ignites when proper combustion air is verified. Featuring a standard 1/4" barb connection, the 26W76 offers a secure fit for rubber pressure tubing to prevent signal loss. This genuine OEM part replaces legacy Lennox 26W7601 units and is a direct substitute for older 34M75 and 17J63 models found in Allied, Armstrong, and Concord furnaces. Built with a heavy-duty housing to withstand high-temperature environments near the collector box, this furnace pressure switch prevents hazard conditions like carbon monoxide leakage by shutting down the ignition sequence if venting is obstructed. For technicians diagnosing a pressure switch open fault, the 26W76 provides a drop-in HVAC replacement part solution that maintains factory specifications for system safety and airflow integrity.

• Precise Calibration: Fixed .40" WC set point ensures exact compliance with Lennox inducer draft requirements.
• OEM Compatibility: Fully interchangeable with Lennox 26W7601 and cross-referenced with 37.69 series catalog numbers.
• Streamlined Installation: Features a 1/4" barb for quick tube attachment and integrated mounting for standard furnace brackets.
• Safety Compliance: SPST design serves as a vital interlock, preventing ignition during vent blockages or inducer failure.

• What causes a Lennox furnace pressure switch to stay open? Most "switch open" faults are caused by blocked vent pipes, clogged condensate drains, or a failing inducer motor that cannot generate sufficient negative pressure.
• Can I use a 26W76 to replace a 26W7601? Yes, these part numbers are technically identical and serve as direct replacements for each other in all Lennox-brand applications.
• Is the 1/4" barb connection universal? While common on most Lennox pressure switches, always verify your existing tubing ID to ensure a vacuum-tight seal on the barb.

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.