A malfunctioning air conditioner, especially on a hot summer day, can be an uncomfortable and frustrating experience. If your air conditioner won’t turn on, it may seem like an urgent problem, but often the issue is something simple that you can fix yourself. Before calling in an expensive repair technician, it’s worth going through some basic troubleshooting steps to see if you can get your AC running again.

In this blog post, we’ll guide you through what to do if your air conditioner won’t turn on, explaining both the simple solutions and when you may need to seek professional help.

1. Check the Power Supply

The first thing to check when your air conditioner won’t turn on is whether it’s getting power. There are a few steps to ensure this:

• Check the Thermostat: If your thermostat isn’t set correctly, it may prevent the air conditioner from turning on. Make sure the thermostat is set to “cool” mode and that the temperature is set lower than the current room temperature.
• Inspect the Circuit Breaker: Sometimes, the issue might be as simple as a tripped circuit breaker. Locate your electrical panel and check if the breaker for the air conditioner is in the “off” position. If it is, switch it back to “on.” If it immediately trips again, it could indicate a deeper electrical issue.
• Examine the Power Switch: Many air conditioners have a power switch near the unit or on the side of the wall. Ensure that the switch is turned on. It’s a simple check but often overlooked.
• Test the Plug and Outlet: For portable or window units, check if the plug is securely connected to the outlet. If the plug seems loose, try a different outlet. It’s also a good idea to plug another device into the same outlet to ensure it’s functioning.

2. Inspect the Air Filter

A clogged air filter can obstruct airflow and prevent your air conditioner from functioning properly. A dirty air filter reduces efficiency, and in some cases, it can even cause the AC unit to shut down completely.

• Locate the Filter: Find the air filter on your unit, which is typically located near the intake side of the unit.
• Remove the Filter: Carefully remove the filter from the unit. If it looks clogged with dust and debris, it’s time to replace or clean it.
• Clean or Replace the Filter: Some filters are washable, while others need to be replaced. If the filter is reusable, rinse it under water and allow it to dry completely before re-installing. If it’s disposable, purchase a new filter and install it according to the manufacturer’s guidelines.

3. Examine the Condensate Drain

Your air conditioner has a condensate drain to remove moisture that is collected during the cooling process. If this drain becomes clogged, it can cause the system to shut down as a safety measure.

• Locate the Drain: Depending on your model, the condensate drain is usually located near the bottom of the air handler or near the outdoor condenser unit.
• Inspect for Blockages: Check if the drain line is clogged or obstructed. If you notice a blockage, you may be able to clear it using a wet/dry vacuum or a plumbing snake.
• Check the Pan: Some units have a pan that collects excess water. Ensure that this pan is clean and free of debris.

4. Test the Capacitor

The capacitor is an essential part of your air conditioning unit. It helps the compressor and the fan motor start up. If the capacitor is faulty, the unit won’t turn on or may turn on and then shut off quickly.

Testing a capacitor usually requires a multimeter and some electrical know-how, so if you aren’t comfortable with electrical components, it’s best to leave this step to a professional. However, if you know how to test the capacitor:

• Turn Off the Power: Always turn off the power to the unit before working with any electrical components.
• Use a Multimeter: Set your multimeter to measure capacitance and check the capacitor for any irregularities. If the reading is outside the normal range, it’s time to replace the capacitor.

5. Look for a Frozen Coil

Frozen evaporator coils can prevent your air conditioner from functioning properly. When these coils freeze, airflow is blocked, and the unit may fail to start.

• Check the Coils: If you suspect frozen coils, inspect the evaporator coils. You may notice ice buildup around the coils.
• Let It Thaw: Turn off the air conditioner and allow the coils to thaw. This can take several hours, so be patient. After the coils have thawed, check the filter and the airflow to ensure nothing is obstructing the airflow.
• Fix the Root Cause: If your coils keep freezing, it could be due to low refrigerant levels, a dirty filter, or inadequate airflow. A professional technician can help diagnose and address the underlying problem.

6. Reset the System

Some air conditioners have a reset button, which can be used to troubleshoot and reset the unit. This button is usually located on the main unit or the thermostat.

• Press the Reset Button: If your air conditioner has a reset button, try pressing it to see if it resolves the issue. Hold it for a few seconds and release.
• Power Cycle the Unit: If no reset button is available, turn the unit off and unplug it. Wait for a few minutes before plugging it back in and turning it on again. This can help to reset the internal electronics.

7. Inspect the Refrigerant Levels

Low refrigerant levels are another common cause of air conditioner problems. If your unit is low on refrigerant, it won’t be able to cool your space properly, and the unit may refuse to turn on altogether.

Low refrigerant is often caused by a leak in the system. It’s important to note that refrigerant should never need to be replaced unless there is a leak. If you suspect refrigerant is low, it’s best to call a professional, such as Boon Keng Aircon Servicing, to diagnose and fix the issue.

8. Call a Professional

If you’ve gone through the steps above and your air conditioner still won’t turn on, it’s time to call in a professional. Air conditioners are complex systems with intricate electrical and mechanical components. A technician will be able to identify the issue quickly and safely. Here are some common problems that require a professional touch:

• Compressor Issues: If the compressor is malfunctioning, it may require replacement or repair. This is a delicate job that involves handling high voltage and refrigerant, so it’s best left to a professional.
• Electrical Failures: Wiring or electrical components can wear out over time, causing the unit to malfunction. A certified technician can safely repair or replace these parts.
• Refrigerant Leaks: If there’s a refrigerant leak, a technician will be able to identify it and refill the refrigerant.

Conclusion

When your air conditioner won’t turn on, it’s easy to feel overwhelmed, but many problems can be fixed with simple troubleshooting steps. Start by checking the power supply, air filter, and condensate drain. If necessary, inspect the capacitor, look for frozen coils, and reset the system. However, if the issue persists, it’s best to contact a professional technician to address more complex problems. By keeping up with routine maintenance and taking care of small issues early on, you can keep your air conditioner running efficiently for years to come.