632489R 0.70" WC SPST Pressure Switch Normal Stock Item Product Overview 632489R is an OEM 0.70 in WC single-pole single-throw (SPST) pressure switch designed to sense inducer draft or differential pressure in gas furnaces and packaged HVAC units. It provides reliable, fast-action switching at a fixed 0.70 in WC setpoint, ensuring the control board receives a positive pressure signal before allowing ignition or maintaining burner operation. Technical Specifications Setpoint: 0.70 in WC (water column) Contact arrangement: SPST, normally open until pressure reaches setpoint Contact rating: 1 A @ 120 VAC (confirm on appliance data plate) Pressure connection: 1/4 in OD hose barb Terminals: dual 1/4 in male spade quick-connect Housing: epoxy-filled die-cast aluminum Ambient temperature range: –40 °F to 175 °F Shipping weight: 0.11 lb Packaged dimensions: 10 × 12 × 12 in, 10 oz Location On-hand Committed Available warehouse 0 0 154 Cross-Reference Part Numbers OEM Part Number Notes 632489R Factory-authorized pressure switch 632489 Original part without revision “R” Compatibility Fits a wide range of Nordyne, Coleman, Concord, Nortek and private-label gas furnaces and packaged units that require a 0.70 in WC SPST pressure switch for inducer draft proving or flame rollout protection. Common applications include: M1 series gas furnaces Single-stage and multi-stage burner assemblies Packaged rooftop units with induced-draft blowers Always verify your unit’s required setpoint and mounting style against the appliance data plate before ordering. Technician Notes De-energize the furnace and shut off the gas supply. Depressurize the inducer housing—verify zero pressure at the switch tubing. Photograph or label the old switch’s tubing and wiring connections. Remove the old switch from its mounting boss and inspect the hose barb for debris. Hand-thread the new 632489R switch onto the boss; torque to OEM specification. Connect 1/4 in tubing and push fully onto the barb; secure with a spring clamp if used. Reattach control wiring to spade terminals, ensuring tight fit. Restore power and call for heat; confirm inducer runs and the switch closes at ~0.70 in WC. If the blower starts but the furnace locks out, verify setpoint with a manometer and check for tubing leaks. Additional Resources Downloadable wiring schematic and installation guide (PDF) Printable pressure-switch cross-reference sheet Step-by-step video: Replacing a 0.70 in WC pressure switch
