Nordyne 632487R Pressure Switch -0.90 WC SPST Furnace Air Switch

The Nordyne 632487R is a negative pressure air switch designed for residential and light commercial gas furnaces. This critical safety component monitors the pressure differential in the furnace venting system, ensuring proper combustion air flow before allowing the furnace to operate.

Key Features:

• Pressure setting: -0.90 inches water column (WC)
• SPST (Single Pole Single Throw) switching configuration
• Designed for use with Nordyne, Miller, Intertherm, and compatible HVAC systems
• Monitors inducer motor operation and draft pressure
• Safety lockout prevents furnace operation with blocked vents or improper draft
• Direct OEM replacement part for reliable performance

This pressure switch is a common replacement component in forced-air furnace systems. When the inducer motor creates the proper negative pressure in the venting system, the switch closes to allow the ignition sequence to continue. If proper draft is not achieved, the switch remains open and prevents burner operation, protecting against potential combustion safety hazards.