Air conditioners are the embodiment of luxury and comfort. For a normal eye it might seem as a very simple machine but in reality it’s a complicated appliance which goes through a number of processes to provide cooling for your houses. But what happens when it stops cooling? Don’t worry because here’s everything you need to know!


How do air conditioners work?

Every model of air conditioner is different but the main parts and components of it are the same. The main parts of the ac include refrigerant, expansion valve, condenser coil, evaporator coil, compressor, etc. Here’s a brief explanation of what these parts do:

Refrigerant: A refrigerant is a fluid which can turn gases into liquid. It is an important part of the air conditioner. It absorbs the heat inside the room and turns it into liquid. Then the liquid is carried through copper coils and cooling tubes to the outdoor unit of the air conditioner. Once the heat is delivered outside, it goes back to its original gaseous state and comes inside the indoor unit. Now that the refrigerant is cool, a small fan blows air on it and it releases cold air inside the room.

Expansion valve: The expansion valve plays a role after the refrigerant starts working. The heat that the refrigerant converts into liquid is still too hot to travel through the evaporator coil. Expansion valves depressurize the liquid and hence the temperature of the liquid drops down rendering it free to travel in the evaporator and other coils.

Condenser coil: Condenser coil is placed in the outdoor unit. It helps the refrigerant to transform and pass the heat into gas again and release it outside.

Evaporator coil: When the small fan inside the air conditioner blows on the cold coils, cool air is released inside the room. While this process takes place, the evaporator coil simultaneously absorbs the heat in the room.

Compressor: For the process of  cooling to take place, the refrigerant’s temperature needs to be raised. This is where a compressor comes in. A compressor pressurizes the refrigerant until the temperature of the refrigerant goes up.


To summarise the working of an air conditioner, the first step is absorbing the heat inside the room and transferring it outside. When the fluid which transfers the heat is back with a very low temperature, the fan blows on it releasing cold air for the room. This cycle continues until the room is cooled and after that any signs of heat inside the room are continued to be absorbed and transferred out of the room through the outdoor unit.


Why isn’t the air conditioner cooling the room?

There are many things that could go wrong with an air conditioner. Figuring out what it is can be quite a task. But it gets significantly easier if you know the reasons. If your air conditioner is running but it’s still not cooling the room then a small process might have a fault or a certain part has stopped working. Let’s see the in-depth problems that might’ve occurred in a situation where your air conditioner won’t cool a room:-

  • Malfunctioning thermostat: This is a very common and possible malfunction which happens while using an air conditioner. Often the settings get changed to manual rather than auto and the fan inside the air conditioner refuses to blow air since the temperature is unknown or it might blow lukewarm air as well.
  • Clogged air filter: The air is passed through the frontal air filters. The chances of this air filter getting clogged because of dirt, debris, etc are very high and likely. And if your air filter is clogged then the air has no outlet to be released from. If you don’t get your air conditioner serviced regularly then this might be the issue. During an air conditioner servicing, the filters are washed and cleaned thoroughly.
  • Damaged refrigerant: The refrigerant plays a very vital role in cooling the room. But sometimes due to manufacturing faults the refrigerant level can be low. There is also the possibility of the fixed refrigerant leaking inside the air conditioner. It is advised to call the professionals and get it checked out before the issue gets bigger.
  • Dirty condenser: Condenser helps the heat to be released outside. If the condenser gets impenetrable due to dirt and debris then the transfer and release of heat is impossible and this will affect the cooling process. Check out the outdoor unit of the air conditioner and find out if the dirty condenser is a problem.
  • Compressor: The refrigerant needs depressurizing to get it’s temperature raised and this is the job of a compressor. It also controls the flow of refrigerant between the condenser and evaporator coils. You will need to replace the compressor if it’s broken.
  • Broken fans: There are 2 fans used in a basic air conditioner. One is placed inside the indoor unit and the other is placed in the outdoor unit. The motor of the fan can be at fault for not working and needs to be replaced immediately. Malfunctioning fans can affect the release of heat and also cold air in the room.


No matter what the problem is, trusting the experts is the right way to go when it comes to fixing the air conditioner. Getting new parts and replacing them with faulty ones can be a dangerous task and might put the whole air conditioner at risk of getting shut down.