Lennox Dual Stage Pressure Switch WC

The Lennox Dual Stage Pressure Switch (also called a two-stage furnace pressure switch or draft pressure switch) is an OEM replacement part for Lennox gas furnaces. It checks that the combustion air inducer is creating enough draft before the burners are allowed to fire. Each switch is rated in inches of water column (WC).

Key Features:

• Two calibrated pressure set points, one for low-fire and one for high-fire operation in two-stage furnaces
• Monitors negative pressure from the inducer to confirm safe combustion airflow before ignition
• Opens the circuit and shuts down the burners if the flue is blocked, the venting is restricted, or the inducer fails
• SPST (single pole, single throw) electrical contacts that signal the furnace control board
• Genuine Lennox OEM design for direct replacement of worn or failed switches

The switch connects to the inducer housing or flue collector box with pressure tubing. It protects the heat exchanger and supports safe, efficient furnace operation. Choose the variant whose WC set points match the original part.