Lennox 15M22 High Altitude Pressure Switch 7,501–10,000 ft

Description

The Lennox 15M22 is a high-altitude pressure switch specifically engineered to ensure safe and reliable furnace operation at elevations between 7,501 and 10,000 feet above sea level. At higher altitudes, reduced air density affects combustion airflow and inducer performance — a standard pressure switch calibrated for sea-level conditions may not trip at the correct differential, creating potential safety risks. The 15M22 is factory-calibrated to the precise setpoint required for high-altitude installations, making it a direct OEM replacement for compatible Lennox furnace models.

Key Features

• Designed for high-altitude installations from 7,501 ft to 10,000 ft above sea level
• OEM Lennox replacement pressure switch — ensures proper fit and calibration
• Factory-set differential pressure setpoint optimized for reduced-density air at altitude
• Monitors inducer motor performance and combustion airflow for safe furnace operation
• Prevents furnace ignition if adequate draft pressure is not established
• Direct drop-in replacement for compatible Lennox furnace models

Why High-Altitude Pressure Switches Matter

At elevations above 7,500 feet, thinner air reduces the static pressure differential that the inducer blower can generate. A standard pressure switch may fail to open or close at the correct threshold, leading to unsafe combustion conditions or nuisance lockouts. The Lennox 15M22 is calibrated specifically for this altitude band, restoring proper safety control behavior without the need for field adjustment.

Application

• Replacement pressure switch for Lennox gas furnaces installed at 7,501–10,000 ft elevation
• Suitable for residential and light commercial Lennox furnace applications
• Always verify compatibility with your specific furnace model number before installation

Installation Notes

Installation should be performed by a qualified HVAC technician. Always disconnect power before servicing. Verify the replacement switch matches the OEM part number and altitude rating required for your installation site.