When your outdoor air conditioning unit refuses to start and only emits a click or hum, homeowners often fear the worst—a dead compressor. However, over 70% of outdoor unit non-start emergencies are caused by a failed start or run capacitor.
The Dual-Run Capacitor: Small Part, Big Job
The capacitor acts as an energy storage battery, providing the high initial electrical boost required to jumpstart the compressor and fan motor. Due to high summer ambient heat and electrical voltage spikes, capacitors degrade and swell over time.
| Feature | Blown Capacitor | Dead Compressor |
|---|---|---|
| Symptoms | Outdoor fan humming, clicking sound, bulged top cap | Hard metallic clunk, circuit breaker tripping, grounded windings |
| Typical Repair Cost | $180 – $350 | $2,200 – $4,500 |
| Repair Time | 20 – 30 Minutes | 4 – 8 Hours (System Burnout Flush) |
| Parts Availability | In-stock on tech truck | May require factory order |