Summer is coming and we all know how essential it is to stay cool during those hot months. But what happens when the dreaded day arrives and your air conditioner isn’t cooling? Before you start panicking, take a deep breath. Fortunately, there are a few simple troubleshooting steps you can take to try and fix your AC unit before having to call in a professional. In this article, we’ll go through some common reasons why your air conditioner might not be cooling, and give you some tips on how to rectify the issue and stay cool during those summer months.

1. Common Causes of an Air Conditioner Not Cooling

If you have an air conditioner that is not cooling, there are several common causes that you should be aware of. These include:

  • Dirty air filter: A dirty air filter can reduce airflow, causing your air conditioner to work harder and cool less effectively.
  • Refrigerant leak: If your air conditioner is low on refrigerant, it may not be able to cool your home properly. Refrigerant leaks can be caused by a variety of factors, such as age, wear and tear, or poor installation.
  • Thermostat malfunction: A faulty thermostat can cause your air conditioner to run too often, not often enough, or not at all. If you suspect a thermostat problem, it’s a good idea to check the batteries and ensure that it is set correctly.
  • Dirty condenser coils: Located outside your home, these coils can become dirty and clogged with debris, reducing the efficiency of your air conditioner.
  • Electrical issues: Faulty wiring or a tripped breaker can prevent your air conditioner from turning on or running properly.

If you think your air conditioner is not cooling due to any of these common reasons, the good news is that they are usually easy to fix. In the next sections, we will explore how to diagnose a faulty air conditioner, the essential tools needed to fix it, and a step-by-step guide on how to tackle the problem.

2. How to Diagnose A Faulty Air Conditioner

If your air conditioner is not cooling, there are several possible causes. Before attempting to fix it, you should diagnose the problem first. This section will guide you through the steps to diagnose a faulty air conditioner.

Check the Thermostat

The first step is to check the thermostat. Make sure it is set to “cool” mode and the temperature is below the current room temperature. Ensure the batteries are not dead, and the thermostat is properly wired. If the thermostat is not the issue, move on to the next step.

Inspect the Air Filter

A dirty air filter can cause air conditioning problems. Dust, dirt, and debris can clog the filter, reducing the airflow. This issue causes your air conditioner to work harder and consume more energy, leading to higher energy bills. Clean or replace the air filter regularly to improve the system’s performance.

Check the Circuit Breaker

If your air conditioner is not working correctly, check the circuit breaker. If the breaker is off, switch it back on, and check if the air conditioner is working. If the breaker trips again, there may be an electrical problem that requires professional attention.

Examine the Condenser Coils

Condenser coils transfer heat from the indoors to the outdoors. If they are covered in dirt and debris, the system works harder, and the cooling capacity reduces. Clean the coils using a soft brush or a vacuum cleaner to remove dirt and debris.

Inspect the Refrigerant Levels

Low refrigerant levels can cause your air conditioner to stop cooling. Check the refrigerant levels and add more refrigerant if necessary. However, low refrigerant levels may indicate a leak in the system or a problem requiring professional attention.

By following these steps, you can diagnose the problem and determine whether you can fix it or need to call for professional help. Knowing how to diagnose a problem saves time and money.

3. Essential Tools Required to Fix an Air Conditioner

To fix an air conditioner that is not cooling, you will need some essential tools. These tools are necessary for diagnosing and repairing common air conditioner problems. You can purchase them at your local hardware store or online.

Here are some of the :

1. Multimeter

A multimeter is an essential tool that helps diagnose problems with an air conditioner’s electrical system. It can measure voltage, current, and resistance. Using a multimeter, you can check the voltage going into the air conditioner and determine if there is a problem with the electrical system.

2. Refrigeration Gauges

Refrigeration gauges are essential for checking the refrigerant levels in an air conditioner. If the refrigerant levels are low, your air conditioner will not cool properly. Refrigeration gauges help you determine the correct amount of refrigerant needed for your air conditioner.

3. Vacuum Pump

A vacuum pump is used to remove air and moisture from the air conditioning system. Without this tool, there may be air or moisture in the system, which can cause it not to cool properly.

4. Refrigerant Scale

A refrigerant scale is used to measure the amount of refrigerant added to the air conditioning system. It helps ensure that the correct amount of refrigerant is added to the system and that it functions correctly.

In conclusion, having the is crucial for diagnosing and repairing common air conditioner problems. These tools will ensure that your air conditioner cools properly and functions efficiently. Remember to prioritize getting highly recommendable tools that will deliver great results.

4. Step-By-Step Guide on How to Fix an Air Conditioner Not Cooling

If you have identified that your air conditioner is not cooling, then it is essential to diagnose and fix the problem as soon as possible. Here is a comprehensive step-by-step guide on how to fix your air conditioner.

Step 1: Turn off the Power
Before starting any work on your air conditioning system, it is critical to turn off the unit’s power. You can do so by shutting off the circuit breaker that controls the air conditioner or unplugging it from the wall socket.

Step 2: Clean or Replace the Air Filter
A dirty or clogged air filter can restrict airflow and cause your air conditioner to malfunction. Start by removing the air filter and cleaning it or replacing it with a new one. Be sure to refer to your air conditioning manufacturer’s instructions on how to replace the air filter.

Step 3: Check the Thermostat Settings
Ensure that the temperature settings on your thermostat are set to a cooler temperature than the room temperature. You can also try lowering the temperature by a few degrees and see if it makes a difference.

Step 4: Inspect the Air Ducts and Vents
Check the air ducts and vents for any blockages or leaks as they can cause airflow problems. Make sure they are clean and unobstructed.

Step 5: Check the Refrigerant Levels
Low refrigerant levels can cause your air conditioner to malfunction. To check the refrigerant levels, you need to consult a professional air conditioning technician.

Step 6: Clean the Outdoor Unit
The outdoor unit of your air conditioner can become dirty and clogged with debris, reducing airflow. Clean the outdoor unit by removing debris, trimming vegetation, and spraying it with a water hose.

Step 7: Call a Professional
If none of the above steps works or you are not confident in fixing your air conditioner yourself, then it is time to call a professional. They can diagnose and fix the problem efficiently and safely.

By following these steps, you can fix your air conditioner that is not cooling and enjoy cool air in your home again.

5. Tips for Preventing Future Air Conditioner Problems

While fixing an air conditioner that is not cooling, you might have discovered the root cause of the problem. But what can you do to avoid future issues and extend the lifespan of your unit? Here are some tips:

1. Schedule Regular Maintenance

Most air conditioner issues are caused by neglecting regular maintenance. You should schedule an annual maintenance checkup with an HVAC professional to inspect and clean your unit. Regular maintenance ensures that your system is running efficiently by detecting any potential problems before they become serious.

2. Replace Air Filters Regularly

To maintain efficient airflow and protect your unit from dirt and debris, you must replace your air filters regularly. Follow the manufacturer’s instructions on how often filters should be changed, but typically, filters should be replaced every 1-3 months.

3. Keep the Condenser Unit Clean and Clear

The outdoor condenser unit of your air conditioner needs to be kept clean and clear of debris. Without proper airflow, the unit can overheat and shut down, resulting in poor cooling, high energy bills, and possible damage to your unit. Ensure that the condenser unit is free of debris, such as leaves, grass or garbage.

4. Install Programmable Thermostats

Programmable thermostats allow you to automate temperature settings, making it easier to keep your home comfortable and energy-efficient. With programmable thermostats, you can set different temperatures for when you’re home or out. This will not only prevent unnecessary wear and tear on your air conditioner, but it will also save you money on your energy bill.

5. Don’t Push Your A/C Unit Too Hard

When it’s hot outside, we all want to keep our homes cool, but blasting your air conditioner at full power might cause it to shut down or overheat. Instead, set your thermostat to a comfortable temperature and give your unit breaks every few hours. Your air conditioner will thank you by running efficiently and lasting longer.

People Also Ask

Why is my air conditioner running but not cooling?

There may be several reasons why your air conditioner is running but not cooling. The most common reasons can include a dirty air filter, low refrigerant levels, or a malfunctioning compressor.

What should I check if my AC is not cooling?

If your AC is not cooling, check the thermostat settings, air filter, and circuit breaker. If these are all in good condition, you may need to check the compressor, refrigerant levels, and evaporator coil.

How do I know if my AC compressor is not working?

If your AC compressor is not working, your unit may not cool or may blow hot air. You may also hear strange noises or notice unusual vibrations. If you suspect your compressor is faulty, contact an HVAC professional to diagnose and repair the issue.

What causes an air conditioner to stop working?

Several factors such as a malfunctioning compressor, low refrigerant levels, electrical issues, or a dirty air filter can cause an air conditioner to stop working.

Can I fix my air conditioner myself?

Some minor air conditioning problems such as cleaning or replacing the air filter can be done by homeowners. However, more complex issues, such as low refrigerant levels or compressor malfunction, require the services of a professional HVAC technician.


If your air conditioner is not cooling, it can be a frustrating experience, especially during hot summer months. By following basic maintenance procedures like cleaning or replacing air filters and routine maintenance checks by a professional HVAC technician, you can avoid many costly repairs and replacements. If you suspect major faults in your air conditioning system, never attempt to fix it by yourself. Always contact and seek professional help.