• Admin
  • 08 Feb, 2023

AC Not Cooling: 7 Major Reasons and How to Fix Them?

Whenever you switch on an appliance, you expect it to work efficiently. However, many times, due to technical or manufacturing reasons, the appliance might suddenly stop working. This can be frustrating. One such example that can greatly affect your comfort in summer is the air conditioner malfunctioning. So if the air conditioner is running 24x7 and you are still sweaty and feel like you are roasting in an oven, this post is for you.

Here we will discuss some of the major reasons why your air conditioner is not cooling and the steps you can take to fix these issues.


Reasons Why Your AC Is Not Cooling Properly


1. Clogged or Dirty Air Filters

One of the major issues with air conditioners is dirty air filters. Do you remember the last time you opened the inner unit and cleaned the filters? If the answer is no, it is likely that your air conditioner is not cooling due to clogged air filters.

The main job of an air filter is to ensure air circulation and also filter the air of dust and debris. However, if they are not cleaned periodically, then the airflow gets restricted. In this case, the compressor has to work harder to cool your room and may stop working within months. Additionally, dirty air filters can also be the reason for many airborne diseases.

Solution: First, check the condition of the air filters and, if required, replace them. You can also clean them with a wet cloth or under running water.

2. Damaged Thermostat or Incorrect Thermostat Settings

If your air conditioner suddenly stops working, you may panic and call an expert. So, first, check whether the thermostat is working properly or not. Incorrect thermostat settings or a defective thermostat could be the reason for your air conditioner's poor performance. If the thermostat system does not work efficiently, your desired temperature will not be achieved.

Solution: You can use a multimeter to test the thermostat. If there is a difference in the reading, you may need to replace it. You can also try switching the auto mode on the thermostat and keep it in auto mode. You can also replace the battery if the thermostat screen is malfunctioning.

3. Faulty Compressor

If the compressor is not working efficiently, you might need to replace it. The compressor is responsible for pressurising the refrigerant and making it flow smoothly through the unit. So if the compressor is not working, the refrigerant will become useless; therefore, your AC will not cool properly.

Solution: Before arriving at any decision, you must carefully inspect the compressor capacitor and the overload protector and check for any defects. If the compressor has died, you’ll need to replace it. You should contact a professional, as there is a risk of severe electric shock.

4. Power Plug and High Voltage Wire

A high-voltage wire connects the outdoor AC unit to switch on. However, if the wire is disconnected, damaged, or loose, your AC will not turn on; there can even be a short circuit. When you switch on the AC, the indoor unit will work; however, the main outdoor unit will not, and therefore you won't get sufficient cooling.

Solution: You can't do anything about it. In this case, you must call a technician who can fix the outdoor unit.

5. Insufficient Refrigerant

Refrigerant is the cooling fluid that is responsible for the cool air. If your AC’s coolant is low, it becomes less pressurised, so you do not get sufficient cooling. In most cases, AC refrigerant shortage is due to a leakage in the AC coil.

Solution: If there is a leakage, there is not much you can do about it rather than calling a professional. This is because refilling the coolant requires technical knowledge, and it is necessary that a professional performs that task. They can also figure out the exact reason for the leakage.

6. Damaged Motor

Do you hear grinding noises when you switch on the AC? If that is the case, then, unfortunately, the motor blades of the outdoor unit are not functioning properly. The outdoor unit is heavily protected to prevent any contact with outside air or dirt. However, due to lack of maintenance, dust can get in at times.

Solution: In such a scenario, you can open the outdoor unit and clean the motor yourself. However, if there is significant damage to the motor blades, it is time to replace it.

7. Excessive Ventilation

Have you ever wondered about the working mechanism of your air conditioner? The AC simply circulates the existing air through its evaporator, chemically cools it, and then circulates it back into the room. The process keeps on repeating until the desired temperature is reached. However, if there are open corners in the room, there will be a constant supply of humid air, and the AC will be unable to cool the room sufficiently.

Solution: Before switching on the AC, close all the doors and windows and switch off any exhaust fans. Not only will your room cool faster, but you will also save a lot on electricity bills.

Tips to Follow to Avoid AC Malfunctioning

Your house's air conditioning system will work best with proper maintenance. Regular maintenance is necessary to keep the appliance in working order when summer strikes. So  before the start of summer, you should contact a technician who can perform the annual maintenance. The specialist can check for proper airflow, refrigerant level, and all the important aspects.

Additionally, while buying a new AC, remember to consider the size of the room. If the air conditioner is not the right size for the room, that will put pressure on the machine and damage it. So, figure out the square footage of the room and then select between 1, 1.5, and 2 ton air conditioners.


You might have one of the best air conditioners in the market. However, all pieces of technology will at some point experience issues. You can always contact the company's licensed technicians to resolve the issues. However, with these solutions mentioned above, you can solve any minor issues of an air conditioner by yourself and not only save some extra bucks but also time.