OEM Carrier Dual Pressure Switch Kit for Model PG9MXA060120AASA — Part 328529-751

This OEM dual pressure switch kit is the factory-specified replacement for the Carrier PG9MXA060120AASA 2-stage gas furnace. The pressure switch monitors negative pressure created by the inducer draft motor to prove safe venting conditions before allowing ignition to proceed. When it fails or sticks open, the furnace will lockout before ignition — often displaying a fault code for "pressure switch open" — leaving you with no heat. A failed pressure switch is one of the most common causes of furnace no-heat calls on 2-stage Carrier equipment.

• Specs: Dual-switch assembly | Burner Enclosure Switch: 0.91" W.C. | Collector Box Switch: 1.58" W.C. min / 1.81" W.C. max | Normally Open (N.O.) position | Includes mounting bracket, tubing assembly, and pressure switch tube
• OEM vs Generic: OEM switches are factory-calibrated to exact W.C. ratings. Off-spec generic switches can trip too early or too late — causing nuisance lockouts, failed ignitions, or dangerous venting conditions. Always use OEM on 2-stage furnaces.
• Install difficulty: 3/5 — Shut off gas and 120V power before beginning. Tools needed: 1/4" and 5/16" nut drivers, needle-nose pliers, and a vacuum/manometer to verify inducer suction post-install. Document existing tubing routing with photos before removal.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse when ordered before cutoff.

Compatibility: Engineered for Carrier model PG9MXA060120AASA 2-stage gas furnace. Also supersedes legacy part numbers HK06NB013 and 326070-701. Verify your existing W.C. rating on the data plate or old switch body before ordering to ensure correct fitment. Have a question? Our HVAC parts specialists confirm fitment before you buy — call or chat today.