How to fix a central air conditioner that trips the circuit breaker

As the summer heat intensifies, there’s nothing more frustrating than turning on your central air conditioner only to have it immediately shut down due to a blown fuse or tripped circuit breaker. This sudden loss of cooling can be incredibly disruptive, leaving you and your family sweltering in stifling indoor temperatures. We’re here to help you get your cooling system back up and running just in time to beat the summer heat.

If you find out that you need any replacement parts for your appliance while you’re troubleshooting, you can enter your model number at AppliancePartsPros.com to order them. Most orders arrive in just two business days, and we have thousands of free guides to show you how to install your new parts.

The troubleshooting information provided in this article may not apply to your specific appliance model. While we strive to offer helpful advice for DIY appliance repairs, variations in models and configurations can lead to differences in troubleshooting steps, error codes and part replacements. For the most accurate guidance, we strongly recommend consulting the technical sheet for your specific appliance model.

Safety precautions

When working on any appliance, remember to keep safety first. Here are some tips to keep in mind: 

• Always power off and unplug your appliance or switch off the circuit breaker before attempting any maintenance or replacement work. This keeps you safe by preventing any risk of injury from electric shock.
• Wear insulated work gloves to protect your hands from sharp metal parts, pinching hazards and debris.
• Take your time and don’t rush while working to prevent accidents and personal injuries.
• Work in a well-lit area so you can clearly see and access the interior parts.
• Clear your workspace of clutter and other obstacles. Keep children and pets away from the work area.
• Never work on internal parts with bare wet hands. Make sure the work area is completely dry.
• Check your user manual to see if there are specific installation or safety instructions for your part or appliance. 
• Be gentle when handling or removing parts. Excessive force might damage the appliance or cause injury.
• Wear safety glasses when working with chemicals, dust or cleaning large debris to prevent injury. 
• If the appliance has recently been used, give it plenty of time for any heating parts to cool down before working on it. 
• Take pictures or make a note of wiring terminals or other connections before disconnecting to prevent any problems with reassembly.
• When working with wires, avoid touching any exposed wires or terminals. If you need to touch a wire, use a non-conductive tool or wear insulating gloves to prevent an electrical shock.

Tools and materials needed

• Multimeter
• Screwdrivers 
• Vacuum cleaner or compressed air

The specific tools required may vary depending on the model of your appliance and the type of fasteners used on it. Always consult the user manual or refer to any specific instructions provided by the manufacturer for the recommended tools for your appliance model.

Troubleshooting steps

Check for circuit overload:

1. Verify that the air conditioner is the only appliance running on the dedicated circuit.
2. Ensure the circuit breaker or fuse is properly sized for the air conditioner’s power requirements, which can typically range from 15 to 40 amps.
3. Consider adding a separate, dedicated circuit for the air conditioner if the shared circuit is overloaded with other high-draw appliances.
4. Avoid using extension cords or power strips, as they can cause voltage drops and overload the circuit.

Inspect the cord and plug:

1. Examine the power cord from the air conditioner to the electrical outlet for any visible damage, cracks, fraying, or excessive wear.
2. Check the plug for proper prong alignment and secure fit in the outlet, and ensure there are no signs of overheating or melting.
3. Test the cord and plug with a multimeter to check for any short circuits or ground faults.
4. Replace the cord or plug if any issues are found, as a short-circuited cord or plug can cause the circuit breaker to trip.

Examine the switches and motors:

1. Turn off power to the unit and remove the access panel to expose the internal electrical components.
2. Inspect the capacitors, contactors, relays, and other electrical switches for any signs of damage, pitting, or corrosion.
3. Test the fan motor and compressor motor for proper resistance and operation using a multimeter.
4. Replace any faulty electrical components that are causing a short circuit or excessive current draw.

Ensure proper restart timing:

1. Wait at least 5 minutes before restarting the air conditioner after it has been turned off.
2. This delay allows the system to properly depressurize and prevents short-cycling, which can cause the circuit breaker to trip due to the high inrush current during startup.

Verify correct fuse size:

1. Check the air conditioner’s nameplate or manufacturer documentation for the recommended fuse or circuit breaker size.
2. Replace the fuse or circuit breaker with the proper size if it is incorrect, as using the wrong size can lead to nuisance tripping.

Inspect the wiring:

1. Examine the wiring from the electrical panel to the air conditioner for any signs of damage, fraying, or loose connections.
2. Check for any wiring that may be shorted or grounded against the unit’s metal frame or other components.
3. Repair or replace any damaged wiring as necessary, ensuring all connections are secure and properly insulated.

Additional information

Thank you for reading! We hope this guide helped you get your central air conditioner working again.

If you have any other appliance repair needs or projects, don’t hesitate to explore our other troubleshooting guides and videos. 

If you need replacement parts or some extra help with ordering them, grab your model number and head over to AppliancePartsPros.com, where you can chat with a pro, read our DIY blog, and more.

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Keep Reading:

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How to Clean Your Air Conditioner the Easy Way 

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