6 Reasons why isn't car air conditioner blowing cold air?

6 Reasons why isn't car air conditioner blowing cold air?

Why isn't my car's air conditioner blowing cold air?

This is a common problem that affects almost every vehicle equipped with an air conditioner. Even after properly configuring the air conditioner, it may stop working or blow hot air. Diagnosis of this problem may be difficult due to the complexity of the vehicle's air conditioning system.

Dealing with the problem becomes even more difficult because it may involve other vehicle components. As a result, it is recommended that you book your car for a scheduled car service in Reading and allow the professionals to fix the problem.

The most common 6 Reasons why isn't a car air conditioner blowing cold air?

1.     Refrigerant Leakage 

The most common cause of AC problems is refrigerant leakage. This could happen at any of the circuit components or connections. The most common source of the leakage is the external condenser. This could be due to an accident that caused a dent in the fluffy fins. Smearing some oil on the leak will help you find it.

2.     Inadequate Cooling Fans

Inadequate cooling fans can wreak havoc on cooling the hot refrigerant emitted by the compressor. The hot refrigerant must cool by flowing inside the condenser due to the impact of the fans blowing cold air.

3.     Faulty Compressor

A faulty compressor prevents the refrigerant from successfully flowing through the AC circuit, resulting in no cold air. The most common cause of compressor damage is leaving it idle for extended periods of time. During the winter, for example, you can turn off the air conditioner.

4.     Blocked Condenser

One of the possible causes of no cold air blowing from the air vents is a clogged condenser. A clogged condenser could be the result of a vehicle driving through mud or sludge in the pipes. This forms a barrier between the refrigerant and the cold air emitted by cooling fans. It eventually causes the refrigerant to stop cooling.

5.     Electrical Issues

An order from the ECU is required for the cooling fan to run at maximum speed in order to cool the engine while turning on the AC and to provide the refrigerant with the cool it requires to operate. It then goes to the fuse box to magnetise a relay, which activates the fan at the proper speed. Turning on the air conditioner thus involves many electrical systems, all of which must be in perfect working order in order to function properly. Any circuit failure, such as a faulty relay, will prevent the signals from reaching the fans. As a result, the engine will not receive adequate ventilation, causing it to overheat.

6.     Failure of the Clutch Cycling Switch

This is a critical component of the AC system. It is situated in the low-pressure zone of the AC. Its purpose is to keep track of the pressure of the refrigerant flow in the system. When the switch detects a drop in pressure below a certain threshold, it allows pressure to flow to the low-pressure area, restoring system pressure to normal. If this switch fails due to a faulty contact or another electrical fault, the entire process will be disrupted. This is due to the switch's responsibility for maintaining a constant pressure in the alternating current circuit.

How Does a Car's Air Conditioning Work?

Let us start by learning how the air conditioning system works, what each component does, and how it affects the system. To enjoy the cold air in your cabin, you must first understand how all of these components interact. The major components of the air conditioning system are as follows:

1.     Refrigerant

While not a system component, it is required for it to function. The refrigerant is the lifeblood of the air conditioning system. It is required for the AC process to be successful by all system components. Refrigerant is available as a gas. At high temperatures and pressures, the refrigerant is a liquid. There are a variety of refrigerant codes, including "R-134A," "R-410A," "R-22," and others. As a result, you should stick to the type that is recommended for your vehicle. To speak with a professional, consult your owner's manual or conduct an online search for full car service near me.

2.     Compressor

The compressor is the beating heart of the air conditioning system. Under high pressure and temperature, the compressor compresses the refrigerant and converts it from a gaseous to a liquid state. The compressor works by connecting to the engine via a drive belt and obtaining rotation from it.

3.     Condenser

The condenser is one of the most delicate parts of an air conditioning system. The condenser is located in the vehicle's front. It resembles a radiator, but it is placed directly in front of it, facing the cooling fans. The primary function of the condenser is to condense the high-temperature, high-pressure refrigerant from the compressor. When the refrigerant flows inside the condenser tubes while facing the cold air blowing from the front of the vehicle, this happens.

4.     Evaporator

The evaporator is the only component found inside the cabin. The remaining parts are kept in the engine compartment. The fins and tubes of the evaporator are similar to those of a small radiator. This component's primary function is to receive cold refrigerant from the drier/receiver. As the cabin air passes through the cold evaporator core, heat is exchanged between it and the outside air. That is when cold air is blown from the air vents in the cabin.

5.     Receiver 

During the preparation stage, the receiver is used. It removes any moisture that has accumulated in the refrigerant while it was in the evaporator. The removal of moisture is important because it prevents the formation of ice, which can lead to component blockage and damage.

6.     Expansion Valve

The primary function of this component is to convert a high-pressure liquid refrigerant to a low-pressure liquid.


Searching online for car air conditioner repair near me and having a car mechanic change the cabin/Ac filter on a regular basis is one simple way to keep the cold air in the cabin. This helps to keep the evaporator clean and free of clogs. If you suspect you have a problem but are unable to diagnose it on your own, you should seek professional help.

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