Air Conditioner Compressor Won T Kick On

Introduction

Is your air conditioner blowing warm air when it should be providing refreshing coolness? A common culprit is a compressor that won’t kick on. The compressor is the heart of your AC system, responsible for circulating refrigerant. When it fails to start, your AC becomes essentially useless. This problem often occurs during peak summer months when your AC is working hardest. Addressing it promptly is crucial to avoid discomfort and potentially more expensive repairs down the line. Let’s get your AC back to its cooling best!

Common Causes of Air Conditioner Compressor Won’t Kick On

Here are some of the most frequent reasons why your AC compressor might be refusing to start:

• Tripped Circuit Breaker: A power surge or overload can trip the breaker connected to your AC unit.
• Dirty Air Filter: A clogged filter restricts airflow, causing the system to overheat and potentially preventing the compressor from starting.
• Frozen Evaporator Coil: Restricted airflow due to a dirty filter can cause the evaporator coil to freeze.
• Faulty Capacitor: The capacitor helps start and run the compressor motor. A weak or failed capacitor is a common issue.
• Refrigerant Leak: Low refrigerant levels can prevent the compressor from starting as a safety measure.
• Overheating: The compressor might be overheating due to poor ventilation or other issues.
• Dirty Condenser Coils: Dirty outdoor condenser coils prevent proper heat exchange and can lead to compressor failure.
• Loose Wiring: Loose or corroded electrical connections can interrupt power to the compressor.
• Defective Contactor: The contactor is an electrical switch that sends power to the compressor. If it’s defective, the compressor won’t start.

Symptoms Checklist

Use this checklist to help pinpoint if the compressor is the real problem:

• The AC unit blows warm air instead of cold.
• You hear a humming sound from the outdoor unit but the fan isn’t running.
• The outdoor unit is completely silent.
• The circuit breaker for the AC trips frequently.
• The fan inside the house blows air, but it isn’t cold.
• Ice is visible on the refrigerant lines.

How to Fix Air Conditioner Compressor Won’t Kick On Step-by-Step Guide

Follow these steps to troubleshoot your AC compressor issue:

1. Check the Thermostat: Ensure the thermostat is set to “Cool” and the temperature is set lower than the current room temperature.
2. Inspect the Circuit Breaker: Locate the circuit breaker for your AC unit in the electrical panel. If it’s tripped, reset it. If it trips again immediately, there’s likely a more serious issue.
3. Replace the Air Filter: A dirty air filter is a common cause of AC problems. Replace it with a clean one.
4. Check for Ice on the Evaporator Coil: Located inside the indoor unit, check for ice buildup. If present, turn off the AC and let the ice melt completely. Then, address the airflow problem (usually the air filter).
5. Inspect the Outdoor Unit: Visually inspect the outdoor unit for any obvious damage, debris, or obstructions.
6. Clean the Condenser Coils: Use a garden hose (with a gentle spray nozzle) to clean the outdoor condenser coils. Remove any leaves, grass, or other debris.
7. Listen for a Humming Sound: If you hear a humming sound from the outdoor unit, it might indicate a capacitor issue. Proceed with caution (see safety warning below).
8. Check Wiring Connections (Proceed with Caution – Power OFF): After turning off the power at the breaker, carefully inspect wiring connections near the compressor for looseness or corrosion. Tighten any loose connections.
9. Test the Contactor (If you’re comfortable and knowledgable with electricity): Using a multimeter, test the contactor to see if it’s properly sending voltage to the compressor when the thermostat calls for cooling. If not, it needs replacing (consider calling a professional).
10. Wait and Retry: After completing these steps, wait about 30 minutes and try turning the AC back on. Sometimes the system needs time to reset itself.
11. Listen to the Compressor Start: When the AC turns on, carefully listen to the compressor. If it’s making unusual noises like grinding or clicking, this could indicate a serious mechanical problem.

Fix the Issue Without Buying Parts

Before considering replacements, try these free fixes:

• Reset: Turn off the AC at the breaker for 30 minutes to reset the system.
• Cleaning: Thoroughly clean the air filter and condenser coils.
• Inspection: Carefully inspect wiring connections for looseness or corrosion.
• Maintenance Basics: Regularly clean the condenser coils and replace the air filter to prevent future problems.

When Replacement Might Be Necessary

If the troubleshooting steps don’t resolve the issue, component replacement might be needed. Common failing parts include:

• Capacitor: A faulty capacitor is a frequently replaced component. Replacement cost ranges from $50 to $200 (USD) installed.
• Contactor: A defective contactor can also prevent the compressor from starting. Replacement cost ranges from $80 to $250 (USD) installed.
• Compressor: Compressor replacement is a major repair, costing $800 to $2500 (USD) or more, including labor. If the compressor itself has failed, it’s often more cost-effective to replace the entire AC unit.

Safety Warning

• Always turn off the power at the circuit breaker before working on any electrical components.
• Avoid working on the AC unit in wet conditions.
• If you are not comfortable working with electricity, call a qualified HVAC technician.
• Be careful around refrigerant lines. They can be extremely cold and cause frostbite.

Tools You May Need

• Screwdrivers (Phillips and Flathead)
• Wrench Set
• Garden Hose with Spray Nozzle
• Multimeter (for testing electrical components – use with caution and knowledge)
• Air Filter

FAQ

Here are some frequently asked questions about AC compressor problems:

• Q: Why does my AC compressor keep turning on and off? A: This could be due to a dirty air filter, low refrigerant, or a faulty capacitor.
• Q: Can I fix a bad AC compressor myself? A: Some simpler issues like a dirty filter or tripped breaker can be fixed DIY. More complex issues require a professional.
• Q: How can I tell if my AC compressor is bad? A: Common signs include warm air blowing, unusual noises, or the compressor not turning on at all.
• Q: How long should an AC compressor last? A: A well-maintained compressor can last 10-15 years.

Conclusion

Troubleshooting an AC compressor issue can seem daunting, but by following these steps, you can often identify and resolve the problem yourself. Remember to prioritize safety and don’t hesitate to call a qualified HVAC technician if you’re uncomfortable with any part of the process. We hope this guide has empowered you to get your AC back in working order! If the issue is beyond your capabilities, it’s always best to seek professional help.

Youtube Video: