Troubleshooting Tips for When Your AC Doesn’t Work: 10 Common Causes and Fixes

Let’s face it, finding your air conditioner isn’t working right in the heat of summer is incredibly frustrating. Understanding the common issues and how to troubleshoot them can put you back in control and see that your space remains comfortable.

In this article, we’ll walk you through tips on what to do when your AC isn’t working, including a deep dive into the cause of AC failures, tips on maintenance, and knowing when to call in professional help.

10 common causes for AC failures and fixes

1. Improper installation

Improper installation can lead to various AC failures, such as inadequate airflow, refrigerant leaks, or electrical issues. To fix this, it is essential to hire a qualified professional who can maintain proper installation and adherence to manufacturer guidelines.

2. Dirty air filters

Dirty air filters restrict airflow and can cause the AC unit to work harder, leading to reduced efficiency and potential system failure. Regularly clean or replace air filters every 1-3 months to maintain optimal performance.

3. Low refrigerant levels

Low refrigerant levels can result in poor cooling performance and may indicate a leak in the system. A certified technician should be called to identify and fix the leak, test refrigerant levels, and recharge the system as needed.

4. Condenser coil issues

Dirty or damaged condenser coils can hinder heat transfer, causing the AC unit to work harder and potentially overheat or fail. Regular cleaning and inspection of the condenser coils by a professional can prevent these issues.

5. Faulty thermostat

A faulty thermostat can cause temperature inconsistencies or prevent the AC from turning on altogether. Checking the thermostat settings, replacing batteries if necessary, or calling a professional for repairs can resolve this issue.

6. Electrical problems

Electrical issues such as blown fuses, tripped breakers, or faulty wiring can disrupt the AC’s operation. Resetting breakers, replacing fuses, or contacting an electrician can help address these problems.

7. Frozen evaporator coils

Frozen evaporator coils can occur due to restricted airflow or low refrigerant levels, causing the AC unit to malfunction. Turning off the AC and allowing the coils to defrost, checking for airflow obstructions, and addressing refrigerant levels can help resolve this issue.

8. Clogged drainage system

A clogged condensate drain line or pan can lead to water leaks or damage to the AC unit. Regularly inspecting and cleaning the drainage system using a mixture of bleach and water can prevent clogs and maintain proper functioning.

9. Fan problems

Issues with the fan motor, fan belt, or fan blades can result in poor airflow or noisy operation. Lubricating moving parts, tightening belts, or replacing damaged components can help resolve fan-related problems.

10. Lack of maintenance

Neglecting regular maintenance can contribute to various AC failures over time. Scheduling annual professional maintenance, including comprehensive inspections, cleaning, and tune-ups, is crucial for keeping the AC system running smoothly and preventing unexpected failures.

What are the common causes of AC failure?

• Improper installation: Improper installation can lead to inadequate airflow, refrigerant leaks, or electrical issues.
• Dirty air filters: Dirty air filters restrict airflow and reduce efficiency, potentially causing system failure.
• Low refrigerant levels: Low refrigerant levels can result in poor cooling performance and indicate a possible system leak.
• Condenser coil issues: Dirty or damaged condenser coils hinder heat transfer and may cause overheating or failure.
• Faulty thermostat: A faulty thermostat can cause temperature inconsistencies or prevent the AC from turning on.
• Electrical problems: Blown fuses, tripped breakers, or faulty wiring can disrupt AC operation.
• Frozen evaporator coils: Restricted airflow or low refrigerant levels can lead to frozen evaporator coils and system malfunction.
• Clogged drainage system: Clogged drain lines or pans can cause water leaks or damage to the AC unit.
• Fan problems: Issues with the fan motor, fan belt, or fan blades can result in poor airflow or noisy operation.
• Lack of maintenance: Neglecting regular maintenance can contribute to various AC failures over time.

How can I check if my thermostat is working properly?

Start by setting the thermostat to a temperature that is significantly different from the current room temperature. You should hear a clicking sound, indicating that the thermostat has registered the change. Then, wait for a few minutes and see if your heating or cooling system kicks on. If it does, it suggests that the thermostat is functioning correctly.

Another way to test is by using a thermometer. Place a thermometer near the thermostat and compare its reading to the temperature displayed on the thermostat. If there is a significant difference, it could indicate an issue with the thermostat’s temperature sensor. You can try adjusting the thermostat settings and observing if the heating or cooling system responds accordingly.

If you notice any irregularities or inconsistencies in the thermostat’s operation, it may be necessary to consult a professional for further inspection or potential repairs.

Can power issues lead to AC malfunctions?

Yes, power issues can indeed lead to AC malfunctions. AC units require proper and consistent power supply to function correctly. If there are power problems, such as voltage fluctuations, electrical surges, or inadequate electrical supply, it can adversely affect the AC system. Insufficient power supply may result in the AC not turning on at all or not running at its full capacity, leading to poor cooling performance.

On the other hand, electrical surges or fluctuations can cause damage to the AC’s components, including the compressor or control board. Make sure that the AC unit is connected to a stable power source and protected by surge protectors or voltage stabilizers to prevent power-related issues that can lead to AC malfunctions. If you suspect power issues are affecting your AC system, it is recommended to consult with an electrician to address and resolve the problem.

What should I look for in case of a refrigerant leak?

• Reduced cooling performance: A refrigerant leak can cause a noticeable decrease in the cooling capacity of your AC system.
• Ice formation: An indication of a refrigerant leak is the formation of ice on the evaporator coils or refrigerant lines.
• Hissing or bubbling sounds: You may hear hissing or bubbling sounds coming from the AC unit, which could be a sign of a refrigerant leak.
• Increased energy consumption: A refrigerant leak can cause your AC system to work harder to achieve the desired temperature, leading to higher energy consumption.
• Warm air blowing: If your AC is blowing warm air instead of cool air, it may be due to a refrigerant leak.
• Oil stains or residue: Look for oil stains or residue around the AC unit, which can be an indication of a refrigerant leak.
• Foul smell: A strong, unpleasant odor near the AC unit can be caused by a refrigerant leak.
• Health symptoms: Refrigerant leaks can release harmful chemicals into the air, causing symptoms like headaches, dizziness, or eye/throat irritation. If you experience these symptoms when the AC is running, it may indicate a refrigerant leak.

How can dirty filters affect my AC’s efficiency?

Dirty filters can significantly impact your AC’s efficiency. When the air filters become dirty and clogged with dust, dirt, and debris, they restrict the airflow passing through the system. This restriction reduces the amount of air that can flow into the AC unit, causing it to work harder to maintain the desired temperature.

The reduced airflow puts additional strain on the blower motor, which can result in increased energy consumption and higher utility bills. Also, the AC may struggle to cool your space adequately, resulting in longer running times and decreased comfort. Dirty filters can lead to the accumulation of dirt on the evaporator coils, reducing their ability to absorb heat efficiently.

This can further decrease cooling performance and potentially cause the AC system to freeze up. Therefore, regular cleaning or replacement of air filters every 1-3 months is essential to maintain optimal airflow and allows your AC to operate efficiently.

How can drainage problems cause my AC not to work?

Drainage problems can cause your AC not to work properly due to various reasons. When the AC unit operates, it produces condensation that needs to be drained away. If there are issues with the drainage system, such as a clogged condensate drain line or a malfunctioning condensate pump, it can lead to several problems.

A clogged drain line can cause water to back up and overflow, potentially damaging the AC unit or surrounding areas. In such cases, the AC may have a safety feature that shuts off the system to prevent further damage. If the condensate drain line is blocked, it can restrict airflow and affect the overall performance of the AC.

Reduced airflow can lead to inefficient cooling and increased energy consumption. A clogged drain line can create a favorable environment for mold or mildew growth, leading to unpleasant odors and potential health issues.

What maintenance tips can extend the life of my AC?

• Regularly clean or replace air filters: Cleaning or replacing air filters every 1-3 months prevents dust and debris buildup, ensuring proper airflow and optimal performance.
• Keep the outdoor unit clean: Regularly remove debris, leaves, and dirt from the outdoor unit to maintain proper airflow and prevent obstruction.
• Schedule annual professional maintenance: Arrange for annual maintenance by a qualified technician who can inspect, clean, and tune-up the AC system to identify and address potential issues before they turn into major problems.
• Clear obstructions around the unit: Make sure there are no obstructions, such as furniture or plants, blocking the airflow around the AC unit both indoors and outdoors.
• Check and clean evaporator and condenser coils: Periodically check and clean the evaporator and condenser coils to remove dirt or debris, allowing for efficient heat transfer.
• Inspect and tighten electrical connections: Regularly inspect electrical connections, ensuring they are tight and free from corrosion to prevent electrical issues.
• Monitor refrigerant levels: Have a professional check refrigerant levels and top-up if necessary to maintain proper cooling performance.
• Lubricate moving parts: Lubricate the motor bearings and other moving parts as recommended by the manufacturer to minimize friction and reduce wear and tear.
• Verify thermostat accuracy: Periodically check the thermostat’s accuracy by comparing its reading with a separate thermometer to ensure proper temperature control.
• Protect the unit during off-seasons: Cover the outdoor unit during extended periods of non-use, such as winter, to protect it from the elements.

How can I detect problems with my AC’s compressor?

First of all, if you notice that your AC is not cooling effectively or if it takes longer than usual to reach the desired temperature, it could be an indication of compressor issues.

Unusual noises coming from the outdoor unit, such as grinding, rattling, or buzzing sounds, may also suggest compressor problems. Another sign to watch for is frequent or repeated circuit breaker trips when the AC is running, which can be an indicator of compressor overload.

If you observe that the air conditioner’s fan is running, but the outdoor unit’s fan is not spinning, it could signify a problem with the compressor. If you suspect any issues with your AC’s compressor, it is recommended to consult a qualified HVAC technician who can accurately diagnose the problem and provide appropriate repairs or recommendations.

Do broken fans affect the cooling efficiency of my AC?

Yes, broken fans can significantly impact the cooling efficiency of your AC. The fans in an AC system play a crucial role in facilitating the circulation of air throughout the unit. There are two main fans: the indoor blower fan and the outdoor condenser fan. If either of these fans is broken or malfunctioning, it can lead to various issues.

A broken indoor blower fan can result in reduced airflow, causing inadequate distribution of cool air throughout your space. This can lead to uneven cooling or insufficient temperature reduction. As a result, your AC may take longer to reach the desired temperature, resulting in discomfort and decreased energy efficiency.

On the other hand, a broken outdoor condenser fan impairs the heat transfer process. The condenser fan helps dissipate heat from the refrigerant, allowing it to cool down and circulate again. If the fan is not functioning correctly, heat buildup can occur, leading to higher refrigerant temperatures and reduced cooling efficiency. This can result in higher energy consumption and potential AC system overheating or failure.

What are the issues related to AC’s coils and how to identify them?

• Dirty coils: Accumulation of dirt, dust, and debris on the evaporator or condenser coils can hinder heat transfer and reduce cooling efficiency. Look for visible dirt or debris buildup on the coils.
• Frozen coils: Restricted airflow, low refrigerant levels, or other issues can cause the coils to freeze. Look for ice formation on the coils or reduced cooling performance.
• Corrosion: Corrosion can occur on the coils over time, especially in coastal areas or environments with high humidity. Look for signs of rust or corrosion on the coils.
• Leaking coils: Coil leaks can lead to refrigerant loss and decreased cooling capacity. Look for oily stains or residue near the coils or a noticeable decline in cooling performance.
• Bent or damaged coils: Physical damage to the coils, such as bent fins or dents, can affect heat transfer and reduce efficiency. Visually inspect the coils for any visible signs of damage.

Is there a need to hire an AC repair professional?

Hiring an AC repair professional is highly recommended in many situations. While there are some basic maintenance tasks that homeowners can handle, complex repairs or issues with the AC system should be entrusted to trained professionals. An AC repair professional has the knowledge, experience, and specialized tools to diagnose and fix problems accurately and efficiently. It is best to hire an AC repair professional when:

1. The AC system is not functioning at all.
2. There are strange noises, such as grinding or rattling sounds.
3. The AC is not cooling effectively or maintaining desired temperatures.
4. There are electrical issues, such as frequent circuit breaker trips.
5. The AC unit is leaking water or refrigerant.
6. Any visible damage or malfunctioning components are observed.

To find reliable and qualified AC repair professionals, you can visit our directory website, Big Home Projects. It offers a comprehensive listing of contractors specializing in various home improvement projects, including AC repair. Using this platform can help you find trusted professionals in your area who can provide the necessary expertise to resolve your AC issues effectively.