Lennox 12L46 SPST Furnace Pressure Switch -.40" WC

The Lennox 12L46 is a single-pole, single-throw (SPST) air pressure switch designed for use in residential and light commercial gas furnaces. This OEM component monitors air pressure within the furnace venting system to ensure safe and efficient operation.

Key Features:

• Pressure rating: -.40 inches water column (WC)
• SPST configuration for reliable single-circuit control
• Dual 1/4-inch barb connections for easy installation
• Genuine Lennox OEM part (full part number: 12L4601)
• Designed to monitor combustion air pressure in venting systems

This pressure switch serves as a critical safety mechanism by preventing the furnace from operating when air pressure falls outside specified parameters. It activates when proper airflow and combustion conditions are detected, helping to prevent issues such as backdrafting, incomplete combustion, and system failures. The switch is designed for direct replacement in compatible Lennox furnace models.

Please Note: This part has been superseded by newer Lennox pressure switches including models 14T64, 24W97, 18L89, and 63K93. Consult your furnace model documentation or an HVAC professional to determine the correct replacement part for your specific unit.