In the scorching summer heat, when one fine day you hop in your car and find the car AC blowing hot air, it is definitely a nasty experience that we can understand. As long as the AC works properly, it is an awesome weapon to kill hotness but when it is not, it will, of course, be a bad and pesky day. You might get an idea that the AC is not working the right way but don’t know where the problem exactly is. Before you call the car dealer for getting it fixed, try checking the below listed common errors that could be the possible reasons behind your car AC blowing hot air.
How Car AC Works?
The AC installed in cars works the same way as AC in your homes or a refrigerator. The system is designed to circulate the refrigerant passing through a closed circuit. It will then compress the refrigerant into a liquid form and evaporate it to produce cooling. The machinery of AC includes condenser, evaporator, compressor, and drier.
Refrigerators are however subjected to fewer extremes of heat because they are not exposed to such a high level of hotness as that of an AC in the car. The AC system in the car has some weak areas like O rings, seals, etc which can shrink or dry out in extreme hotness. This results in loss of cooling over time. An average car AC system loses 10% of refrigerant in a year.
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Reasons Why Car AC Blowing Hot Air
Reduced Level of Refrigerant
As discussed above, the main source of cooling is refrigerant. Reducing the level of refrigerant is usually the most common reason behind hot air is blowing from your car’s AC. Refrigerants actually wipe out the heat and make arrangements for the elements that generate cooling.
It is, of course, when the level of refrigerant goes down, it will not be able to combat the excess heat. As a result, the excess heat emitted out of the system in the form of hot air.
If an airtight AC system is installed in your car, you don’t need to refill the refrigerant because the refrigerant will not find any escape route there. It can not evaporate. So, in such cases, the only reason for the reduced level of refrigerant is the leaking system, if any.
Identifying where leakage is an actual problem. Let us give you a little brief of it here. When the refrigerant is coming out, it is in the gaseous state. When it enters into the compressor, it converts into the liquid form. It will then enter into the condenser where the excess heat is emitted by the liquid refrigerant. Again, the refrigerant turns into a gaseous form before it finds a way to the evaporator.
Refrigerant instantly converts into the gaseous form from the liquid state in the least pressure. As the leakage is caused inside the system, it takes no time for a liquid refrigerant to get converted into a gaseous form. This becomes very difficult to find the exact area where the leakage is.
This leakage may be anywhere be it hoses of the system, or compressor or the condenser. So, this becomes a matter of experts who can only find the exact place where the leakage is present. Ordinary drivers or a passenger may find it hard to identify where the problem exactly lies.
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Defect in the Condenser
The condenser is responsible for cooling down the liquid refrigerant coming out of the compressor. This process takes place before the refrigerant converts into the gaseous form. The primary task of the condenser is to remove excess heat from the refrigerant. We can compare a condenser with a radiator. In the AC system, in front of the condenser, two fans are installed to remove the heat from the liquid refrigerant.
Now, there are two possible reasons that cause the car AC blowing hot air. Either there is a blockage in the tubes inside the condenser or if the condenser is broken.
In the first instance when there is a blockage in the tubes of the condenser, prohibit the system to perform its functions ideally. So, in that case, the hot liquid refrigerant will remain hot because the condenser is not able to take out the heat which is its main function. That’s the reason, your car AC vent dispatches hot air in the passenger cabin.
The second case is a broken condenser. If the condenser is broken, it leaks the refrigerant from the puncture tubes of the condenser. Even if there is no leak, there are chances that other parts of the condenser are broken hence unable to perform its basic function of removing excess heat from the liquid refrigerant.
It is hard to find the problem with the condenser by a person who is not well versed in handling such machines. An AC technician, therefore, finds it suitable to connect with who will either repair it or if the condenser is broken, it has to be replaced.
Fault in the Compressor
A compressor is a very important element in the complete functioning of an AC system. It is a compressor through which the refrigerant flows in the system passing through tubes, hoses, and interconnected devices. The flow of refrigerant is only possible through a compressor. Without it, the AC system can’t run. If there is any fault in the compressor, the AC will not stop working however, the AC vent blows hot air which ultimately does not resolve the purpose of installing an AC in the car.
If a car AC will not be used for a long time, it can cause damage to the compressor. Initially, the quality of the compressor service will be co promised and then gradually it starts deteriorating the complete system. There could be other reasons for non-functioning compressors but the major one is not keeping your AC in working condition. Technicians, therefore, recommend Tu to turn on the AC at least in a month on full blast as long as 10 to 20 minutes. It will be great if you will turn on it on a daily basis for a few minutes. Even in the winter days, this trick is helpful.
Broken Cooling Fans
The role of cooling fans is equally important in the efficient working of an AC just like that of compressor and condenser. Cooling fans are found in front of the condenser. They play a very important role in removing the heat from the liquid refrigerant. If the cooling fans are broken they will not be able to perform the desired function and hence your AC blows hot air.
Cooling fans are not so robustly built that they are expected to survive the adverse conditions. They can even be affected if hit by road debris. So, if unfortunately, the cooling fans are broken, there is no way except to replace it. Apart from that, there may be other issues inside the cooling fan say if the fuse is broken or any electrical failure.
If everything mentioned above is working the way they are expected to then probably the problem lies in electrical connections. The car AC runs on electricity and you can’t diagnose the problem at the initial stage unless a fault occurs. The problem with the electrical lies anywhere from the fuse box to the other end connected with the different components of AC. Moreover, the wires are covered with a protective layer hence detecting any fault will be a matter of experts only.
However, there are certain wires that can be detected by normal inspection or the wires where you can reach easily. If the usual workaround resolves the problem, then you can do it yourself but if that doesn’t resolve the issue, the last option remains to consult with an auto mechanic.
AC is amazing equipment and a gift of technology that cools you down especially on a hot summer day but if it’s not working, it is really a bad day. And the reason is the reducing level of refrigerant which is the key to the operation of any air conditioner. The low level of refrigerants may be due to a faulty compressor, bad condenser, broken cooling fans, or electrical problem. Some of the commonly possible reasons are given above to help you out in finding exactly the problem is.