632491R Nordyne Pressure Switch
632491R Nordyne Pressure Switch
Product Overview
632491R is an official OEM Nordyne pressure switch designed to monitor inducer draft in residential gas furnaces. It features a single pole, single throw contact that closes when a vacuum of –1.50" WC is reached, ensuring safe ignition and combustion control.
Technical Specifications
| Specification | Detail |
|---|---|
| Part Number | 632491R |
| Pressure Set Point | –1.50" WC (activates at –1.50 inches water column) |
| Maximum Make Point | –1.70" WC |
| Contact Type | SPST (Single Pole Single Throw) |
| Connection | 1/4" barbed tube |
| Housing Material | High-impact thermoplastic |
| Mounting Bracket | Integrated zinc-plated steel |
| Weight | 0.08 lb (36.3 g) |
Specifications compiled from OEM data and industry references. Pressure switch set point and contact type from SupplyHouse. Connection details from Neuco listings. Maximum make point from Intertherm cross-reference.
Cross-Reference Part Numbers
| OEM Part Number | Notes |
|---|---|
| 632491R | Current OEM Nordyne pressure switch |
| 632491 | Original non-R version; often superseded |
Compatibility
Fits Nordyne, Miller-Nordyne, Nortek Global HVAC, and Intertherm furnaces originally equipped with a –1.50" WC pressure switch. Common applications include:
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Nordyne CMF95, M8 series single-stage induced-draft gas furnaces
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Intertherm M4RL mobile-home furnace models
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Miller-Nordyne CF and CT series light-commercial furnaces
Always verify the appliance’s data plate for pressure switch requirements before ordering.
Technician Notes
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De-energize electrical power and shut off gas before servicing.
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Inspect the existing 1/4" vacuum tubing for cracks or blockages; replace if necessary.
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Mount the new switch on the furnace’s bracket, ensuring the barb is fully seated in the tubing.
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Reconnect the SPST terminals according to the wiring diagram or service manual.
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Restore power and initiate a heat call; confirm inducer motor starts and switch closes at –1.50" WC.
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Use a manometer to verify opening and closing pressures: switch should open above –1.50" WC and close below –1.70" WC.
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Check for vacuum leaks around the barb and switch housing