Where to Buy a Capacitor for an Air Conditioner

Is Your AC Not Cooling? A Faulty Capacitor Could Be the Culprit

If your air conditioner is humming but not starting, running weakly, or shutting off unexpectedly, there's a good chance the capacitor has failed. Capacitors are one of the most common — and most replaceable — AC components. The good news: you don't need an HVAC technician to source the part.

What Does an AC Capacitor Do?

Your air conditioner relies on two types of capacitors:

• Start capacitor — provides the initial burst of energy to start the compressor or fan motor.
• Run capacitor — keeps the motor running efficiently once it's started.
• Dual run capacitor — handles both the compressor and the condenser fan motor in a single unit.

When a capacitor fails, the motor it supports can't start or run properly — leading to warm air, short cycling, or a completely dead unit.

Signs Your AC Capacitor Has Failed

• AC hums but won't start
• Fan spins slowly or only when manually pushed
• Unit shuts off shortly after starting
• Higher than normal energy bills
• Capacitor is visibly bulged or leaking

How to Find the Right Replacement Capacitor

Before ordering, locate the capacitor's specifications on the label of the old part or in your unit's service manual. Key specs to match:

• Capacitance (µF/MFD) — must match exactly (e.g., 45/5 µF for a dual run cap)
• Voltage rating — must meet or exceed the original (e.g., 370V or 440V)
• Shape — round or oval (interchangeable with the right bracket)

Where to Buy an AC Capacitor in Canada

You have a few options when sourcing a replacement capacitor:

• XPart Supply — Canada's go-to source for OEM and premium aftermarket HVAC capacitors. We stock run capacitors, start capacitors, and dual run capacitors for major brands including Carrier, Lennox, Trane, Goodman, and more. Fast shipping across Canada.
• Local HVAC supply houses — may carry common sizes but often require a trade account.
• Big box hardware stores — limited selection, rarely stocked with exact-match specs.
• Online marketplaces — wide selection but quality and spec accuracy can vary significantly.

For guaranteed spec accuracy and reliable parts, ordering directly from a specialized parts supplier like XPart Supply is the safest bet — especially when you need the right µF rating the first time.

Can I Replace an AC Capacitor Myself?

Yes — capacitor replacement is one of the more DIY-friendly HVAC repairs, but it requires caution. Capacitors store a high-voltage electrical charge even after the unit is powered off. Always discharge the capacitor safely before handling it. If you're not comfortable working with high-voltage components, contact a licensed HVAC technician.

Shop AC Capacitors at XPart Supply

Browse our full selection of air conditioner capacitors — including dual run, start, and run capacitors — with same-day shipping on in-stock orders. We serve DIY homeowners and HVAC professionals across Canada.

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