When your AC stops working, it can quickly turn a comfortable day into a frustrating experience. Whether it’s a sudden lack of cooling or strange noises coming from the unit, knowing what to do can make a big difference in preventing further damage and restoring comfort to your home.
This guide will walk you through the steps to take when your AC stops working properly, from basic troubleshooting to knowing when it’s time to call a professional.
Step #1: Turn Your Unit OFF
To shut off your AC unit, locate the thermostat and turn it off completely. Then, switch off the power at the breaker panel or use the outdoor disconnect switch near the unit. This ensures the system is completely powered down, preventing further damage while you inspect the system or wait for professional help.
It’s important to turn off a malfunctioning unit to stop it from damaging itself. Continuing to run the unit can strain its components, such as motors and compressors, leading to overheating or accelerated wear. If the system is frozen or humming but not actively working, leaving it on can worsen the issue and potentially result in more expensive repairs.
By shutting the unit down, you allow it to defrost if needed and avoid unnecessary stress on the system. This not only protects the AC from additional damage but also ensures a safer environment for troubleshooting.
Reasons to Shut Off Your Malfunctioning AC Unit
Step #2: Visually Inspect The Unit
Visually inspecting a unit can give you some clues to what the issues might be, and how severe they are. Different signs warrant different approaches, and distinguishing them can be critical. You can take our signs your AC needs repair article for more potential symptoms.
Ice or Frost On The Unit
Ice forming on the line set or compressor typically signals restricted airflow or coolant issues. What can happen in the case of restricted airflow is that the unit isn’t able to distribute the coldness it’s producing. This means that the coils will become colder and colder, causing ice to form. This will also happen with a malfunctioning blower motor, as it is the component responsible for creating airflow, and distributing cool air around your home. Dirt or dust on the compressor coils may also cause problems as dirt can serve to insulate the coils, preventing the cold from transferring effectively. This makes it important to hose off the unit or otherwise clean it.
In the case of low coolant levels, the leaking coolant causes frost because of the drop in pressure inside the unit, in much the same way a can of compressed air gets colder when it’s used. Another issue may be that the thermostat is giving the air conditioner bad instructions, making it cool more that it’s supposed to, freezing the coils.
If you’re suffering from ice or frost, then you may have a good shot at repairing the unit through the steps below. Otherwise, you should contact a professional.
Unit Humming, But Not Running.
A humming sound without proper operation often points to an electrical issue, such as a failing capacitor or motor. The hum is produced when an electrical component is receiving power, but isn’t functioning properly. It’s most likely caused by a faulty capacitor, as capacitors can’t easily handle Arizona’s summers without a lot of wear. Luckily capacitors are inexpensive, unlike motors or compressors, which are usually too expensive to repair. Thus, If your motor or compressor fails it might be a good time to get a new unit. Humming could also be caused by issues with poor or inconsistent voltage, or bad electrical relays.
Grinding or other strange noises
Loud, grinding noises from the unit could indicate mechanical problems like a failing motor or loose parts. It could be that a wire is being hit by the fan, a screw is rattling around, or any number of mechanical malfunctions. In order to find what the source of the noise is, you would have to open the unit up, which is hazardous for homeowners who aren’t trained in working with AC.
Step #3: Check Your Thermostat
If your AC stops working, and is having problems with freezing, the issue could be as simple as a broken thermostat. Start by checking if the thermostat is working properly, as it instructs the AC how to function properly. Ensure the thermostat is set to “cool” and the desired temperature below the current room temperature. Replace the batteries if needed, and confirm it’s securely mounted and turned on. You may also dust off all surfaces of the thermostat to make sure no dust or debris is causing problems. If you’re handy and careful, you might check the inside of the thermostat to make sure all wires and connections are secure.
Step #4: Clean The Unit
When your AC stops working, sometimes dirt can be a culprit. For the best chances of a working AC you should clean the outside and inside of the system. We have a guides on how to clean your outdoor condenser coils and your indoor evaporator coils, that you can refer to for in-depth instructions.
Step #5: Replace Your AC's Air Filter
A dirty air filter restricts airflow, forcing your AC to work harder and reducing its efficiency. It can cause uneven cooling, freeze the coils, or strain the system, leading to potential breakdowns. When your AC malfunctions it’s good to replace the air filter. That way you can narrow down the potential causes of failure.
Assuming that the unit is turned off, you can locate the filter near the return air duct on the unit. Remove the dirty filter, while noting its size; Replace it with a new filter, ensuring the airflow arrows point in the right direction.
Step #6: Turn The AC Back On
After replacing the air filter and ensuring the thermostat is functioning properly, turn the unit back on to test its performance. Observe for consistent airflow, cooling efficiency, and any unusual noises. If the system operates smoothly, the issue may be resolved; otherwise you should turn it back off, and contact a professional.
What To Do If Your AC Doesn't Start Working
If your AC doesn’t start functioning after troubleshooting, it’s time to call a professional. Avoid running the system further to prevent damage. Describe the issues you’ve noticed to the technician to help them diagnose and resolve the problem more efficiently.
What To Do While Waiting For Your AC to be Fixed
Arizona can be tough without an AC, especially during summer, but there are ways to stay comfortable until it’s repaired. Start by closing blinds or curtains to block out sunlight and reduce indoor heat. Use ceiling and portable fans to circulate air, and place a bowl of ice in front of a fan for a cooling effect. Drink plenty of water to stay hydrated and to avoid heat-related illnesses.
If the heat becomes unbearable, consider spending time in cooler public spaces like libraries, malls, or community centers. Limit strenuous activities during the hottest parts of the day and focus on staying in shaded or well-ventilated areas. These strategies can help you manage the heat while waiting for your AC to be fixed.
Dealing with a malfunctioning AC can be frustrating, especially in extreme heat, but taking the right steps can prevent further damage and help restore comfort quickly. Start by turning off the unit, inspecting for visible issues, and performing basic troubleshooting like checking the thermostat and air filter. If problems persist, call a professional to ensure the system is repaired safely and efficiently. If you’d like to see more about our service check out our AC repair page.
