OEM Carrier Single Run Capacitor P291-1003 for Model PF4MNA030T00AAAA

This OEM single run capacitor (part number P291-1003) is the factory-specified replacement for the Carrier PF4MNA030T00AAAA air handler/fan coil unit. A single run capacitor provides a continuous phase-shifted current to keep the blower motor or condenser fan motor running efficiently after startup. When this capacitor weakens or fails, you'll notice symptoms such as a humming motor that won't spin, sluggish fan startup, frequent short-cycling, or a complete failure of the motor to run — all signs that the capacitor can no longer maintain the electrical field needed to sustain rotation.

• Specs: Single run capacitor | Factory-matched MFD rating | 370V/440V rated (verify data plate) | Round or oval case per OEM specification | ±5% tolerance for reliable motor performance
• OEM vs Generic: This is a genuine OEM Carrier part (P291-1003), manufactured to exact factory tolerances. Generic or aftermarket capacitors often carry a wider ±10% MFD tolerance, which accelerates motor winding stress, reduces efficiency, and shortens overall motor and system lifespan.
• Install Difficulty: 2/5 — A straightforward swap for experienced DIYers or technicians. Always shut off power at the disconnect and breaker before beginning. Discharge the capacitor fully using an insulated resistor or discharge tool before touching terminals. Tools needed: flathead and Phillips screwdrivers, 1/4" nut driver, needle-nose pliers, and a multimeter to verify capacitance. Photograph all wiring connections before removal.
• Warranty: 1-year OEM manufacturer warranty against defects. In-stock units ship the same business day from our NationalHVACParts.com warehouse — get back up and running fast.

Compatibility: Designed and factory-matched for the Carrier PF4MNA030T00AAAA unit. Always verify the MFD and voltage rating printed on your existing capacitor and on the unit's data plate before ordering to confirm an exact match. Our HVAC parts specialists are available to verify fitment before you buy — contact us with your model and serial number for a confirmed match.