AC Repair Guide

AC Capacitor Replacement: Signs, Costs & What to Expect

Updated January 2026 • 5 min read

What Does an AC Capacitor Do?

Think of the capacitor as a battery that gives your AC motor the initial jolt of energy it needs to start. Your AC has two types:

• Start Capacitor: Provides the initial boost to start the compressor
• Run Capacitor: Keeps the motor running smoothly once started

Texas heat is particularly hard on capacitors. The extreme temperatures cause them to degrade faster than in milder climates.

Signs Your Capacitor is Failing

Can You Replace a Capacitor Yourself?

We don't recommend it. Capacitors store electrical charge even when the power is off. A charged capacitor can deliver a serious shock. Licensed technicians know how to safely discharge capacitors before handling them.

What to Expect During Replacement

When we diagnose a bad capacitor, here's what happens:

1. Diagnosis: We test the capacitor with a multimeter and photograph the readings
2. Documentation: We show you the bulging or leaking capacitor (if visible) and explain the issue
3. Replacement: We install a new capacitor with the correct specifications
4. Testing: We verify the system starts and runs properly

The entire process typically takes 30-60 minutes.

How to Prevent Capacitor Failure

• Annual maintenance: We check capacitor health during routine service
• Shade your outdoor unit: Reduces heat stress on components
• Keep the area clear: Good airflow prevents overheating
• Address electrical issues: Voltage fluctuations damage capacitors