AC Capacitor Replacement Cost

A capacitor gives the compressor and fan motors the jolt they need to start. It is one of the most common AC failures and one of the cheapest to fix. Angi puts the average at $250, with a range of $200 to $400 including the part and installation.

Part prices

Source: Angi. HomeGuide gives a part range of $15 to $80.

A dual-run capacitor serves both the compressor and the outdoor fan motor in one can.

Labor

The part is cheap; the visit is not. Angi lists labor at $200 to $400, and says many pros charge an all-in flat rate of $300 to $600. HomeGuide lists the service call at $75 to $200, standard labor at $75 to $150 per hour, and nights and weekends at $160 to $250 per hour.

Signs of a bad capacitor

• The outdoor unit hums but the fan does not spin.
• The AC takes several tries to start, or shuts off soon after starting.
• Warm air from the vents while the outdoor unit makes noise.
• A capacitor that is visibly bulging or leaking.

DIY

Angi estimates DIY parts and tools at $60 to $100. Capacitors store a dangerous charge even with the power off, so this is only for people comfortable discharging and testing them safely.

Related parts

If the fan or compressor still will not start after a new capacitor, the motor or compressor may be the problem. See AC compressor replacement cost and AC repair cost.

Ways to save

• Have the technician test the capacitor during a tune-up; a weak one can be replaced before it fails.
• Ask for a weekday appointment rather than an after-hours call when the house is not dangerously hot.

What the capacitor does

An air conditioner's run capacitor stores and releases electrical energy to start and keep the compressor and outdoor fan motor running. Many units use a dual capacitor that serves both. When a capacitor weakens or fails, the motors struggle to start or do not start at all.

More on signs of a bad capacitor

• The outdoor unit hums but the fan does not spin.
• The AC takes several tries to start, or shuts off soon after starting.
• Warm air from the vents while the indoor blower runs.
• A bulging or leaking capacitor when the panel is opened.

Why it is a common repair

Capacitors wear out with heat and age, and they are one of the most frequent causes of an AC that suddenly stops working on a hot day. The part itself is inexpensive; most of the cost is the service call and diagnosis.

Safety

Capacitors hold a charge even when power is off and can deliver a dangerous shock. Replacement should be done by a technician who knows how to discharge the capacitor safely and match the correct microfarad and voltage rating.

What else the technician may check

A failed capacitor can be a symptom. A good technician also checks the contactor, the fan motor and the compressor's amp draw, because a motor that is failing can kill a new capacitor quickly.

Questions to ask

1. Was the capacitor tested with a meter, and what reading did it show?
2. Is the replacement the same rating as the original?
3. Are the contactor and fan motor in good condition?

In Texas

Long, hot Texas summers mean air conditioners run for many hours a day, and outdoor units sit in direct sun. Heat is hard on capacitors, which is why capacitor failures are one of the most common AC service calls in Texas during peak season.

Start, run and dual capacitors

An air conditioner can have more than one capacitor, and knowing which one failed explains the quote.

• Run capacitor. Keeps the compressor and fan motor running efficiently once they start. Most outdoor units have one.
• Dual run capacitor. A single round or oval can that serves both the compressor and the outdoor fan. It has three terminals, usually marked for the compressor, the fan and a common connection. This is the most common part replaced on residential systems.
• Start capacitor. Gives the compressor an extra boost at startup. Not every system has one. Some technicians add a hard-start kit, which includes a start capacitor, to help an older compressor start more easily.

Each capacitor is rated in microfarads (µF or MFD) and volts. The replacement must match the microfarad rating listed on the old part or the equipment label, and its voltage rating must be the same or higher.

How a technician confirms the problem

A capacitor can look normal and still be weak. The technician turns off power at the disconnect, discharges the capacitor safely and measures its capacitance with a meter. If the reading is well below the rated value, the part is failing. They usually also check the contactor, the fan motor and the compressor's current draw, because a capacitor that failed early may have been stressed by another problem.

Bulging tops or leaking oil are obvious signs of failure, but many failed capacitors show no visible damage.

Why capacitors fail in hot weather

Heat is the main enemy of capacitors. Outdoor units that sit in direct afternoon sun, run for long hours during heat waves or have dirty condenser coils run hotter, and the capacitor ages faster. Power surges from storms can also damage capacitors. This is why many capacitor calls come in the middle of summer, often on the hottest days.

What happens if you keep running a weak capacitor

A weak capacitor makes the compressor and fan motor work harder to start and run. The system may hum, start slowly or trip the breaker. Over time, the extra strain can overheat the compressor or the fan motor, which are far more expensive repairs. Replacing a failing capacitor early is cheap protection for the larger parts.

Sources

1. Angi: How Much Does AC Capacitor Replacement Cost? (updated Aug 3, 2026)
2. HomeGuide: How Much Does AC Repair Cost? (Aug 22, 2025)