How does the car air conditioning system work and what are its parts?

Vehicle air conditioning systems consist of air conditioning and heating. This page describes how the vehicle air conditioning system works, air conditioning system components and failures. Before mentioning the malfunctions of the air conditioning system, it is necessary to explain how they work. Particularly in the summer we need the vehicle air conditioning system is a must for the comfort of the driver and passengers.

Car air conditioning systems that help us cool down in the summer and protect us from the effects of heat. Today, air conditioning is used as standard in every package and model of the cars produced. Auto air conditioning system works on the same principle as the system in refrigerators.

* Vehicle air conditioning systems are just one of the parts that make up the car and other parts and systems to look at the car parts and tasks page.

What Are Air Conditioning System Parts?

Vehicle air conditioning system;
– Air conditioning gas: The fluid circulating in the system.
– Air conditioner Compressor oil: It is a special oil used for lubricating the compressor.
– Compressor: Refrigerant has the task of pressurizing.
– Condenser: It is called air conditioner radiator. It contributes to the fluidization of the fluid.
– Dehumidifier filter: It takes moisture that may occur in the refrigerant and provides it to be sent dry.
– Expansion valve: It helps cool the environment by passing refrigerant from liquid state to gas.
– Evaporator: This is the area where cooling operation is performed.
– Air conditioning fan: Blows air into the vehicle.
– Sensors: They are used to monitor the condition of the air conditioner.
consists of parts. It will be explained in detail below.

I – Vehicle Air Conditioning System What is Air Conditioning Gas and What Does it Do?

R134A gas is used in auto air conditioning systems. The amount of refrigerant is very important for the performance and operation of the air conditioning system. Excessive quantity also affects the performance of the air conditioning system as badly as it does in small quantity. Therefore, it should be ensured that there is an east amount of air conditioning gas.

II – Vehicle Air Conditioning System What is Air Conditioning Compressor Oil and What Does it Do?

A / C compressor oil is the fluid that lubricates the compressor during operation. Use special air conditioning oil. When using R134a refrigerant gas, PAG = Poly-Alkylene-Glycol synthetic oil is used. The air conditioning gas dissolves in the air conditioning oil. For this reason, when checking the A / C gas during air conditioning maintenance, the amount of oil must be checked. In order to fully understand the level, the air conditioner should be checked after a certain period of time. If necessary, add oil.

III – Vehicle Air Conditioning System What is a compressor and what is it?

It is a kind of pump that pressurizes the low pressure refrigerant gas coming from the evaporator and presses it to the condenser. The motor must start in order for the compressor to start because it receives the drive from the motor. When the engine is running, the pulley will rotate in the compressor as it is connected to the compressor by the v-belt. But the compressor is not activated. In order to activate the compressor, you must press the AC button. When you press the A / C button, the compressor will be electrified and the pulley will not turn empty and the compressor will start rotating. The compressor which starts to work pressurizes the refrigerant gas and sends it to the air conditioner radiator.

IV – What is a car air conditioning system condenser and what is it?

The pressurized refrigerant gas coming from the compressor enters the air conditioning radiator, in other words the condenser. Thanks to the air conditioner radiator fan, the refrigerant gas entering the condenser liquefies and exits the condenser. The refrigerant, which is still pressurized, will go to the expansion valve. The task of the air conditioning radiator is to condense the refrigerant gas and make it liquid.

V – What is Car Air Conditioning System Moisture Filter and What is it?

The refrigerant exiting the condenser passes through the dehumidifier filter before going to the expansion valve. The task of the moisture-retaining filter is to remove moisture from the liquid air conditioning refrigerant from the condenser. There is strainer and desiccant inside the moisture catching filter. Here water and impurities are separated from the cooling gas. The moisture trap filter must be replaced within certain periods. The causes of air conditioning failures are mentioned in the section.

VI – What is Car Air Conditioning System Expansion Valve and What is it?

The expansion valve is the needle valve as the valve type. It opens and closes according to the temperature and provides the passage of coolant. The refrigerant that comes to the expansion valve will turn into a mixture of liquid and gas as it passes through the expansion valve. The refrigerant liquid-gas mixture exiting the expansion valve will enter the evaporator. In short, the expansion valve sends the high-pressure refrigerant to the evaporator by reducing the pressure and allowing it to become gaseous. The electric expansion valves have a temperature sensor at the outlet of the evaporator, the cooling liquid entering, the heating leaving; The temperature sensor senses this amount of heating, sends a signal to the expansion valve, and the expansion valve increases or decreases the amount of air conditioning gas passing through.

VII – Vehicle Air Conditioning System What is Evaporator and What is it?

At low pressure, the incoming gas-liquid mixture enters the evaporator and will completely become gas until it exits. During the transition from this liquid to gas, it takes the ambient temperature and exits the evaporator. Evaporator is the leading part for cooling the environment. Lowers the ambient temperature.

VIII – Vehicle Air Conditioning System What is Air Conditioning Fan and What Does it Do?

The air conditioning fan is the part that allows the fresh air to be blown into the vehicle. Blows the air from the atmosphere or inside the car into the car. This blown air passes through the evaporator grids and is cooled. The cooling air will also cool the vehicle interior.

The refrigerant gas in the evaporator, which provides the cooling of the air blown by the air conditioning fan, will come back to the compressor inlet as low pressure and completely gaseous and complete the cycle. The compressor then pressurizes the refrigerant gas back to the condenser. The cycle will then continue until you turn the air conditioning knob off. When you turn the A / C knob off, the compressor power will be cut off and the pulley will start to idle. In other words, the pistons in the compressor will remain constant.

Average temperature and pressure values ​​of the air conditioning gas circulating in the air conditioning system

Compressor outlet pressure can be between 14 bar and 18 bar, temperature increases to 65 degrees.
The inlet pressure of the compressor can be 1.0 bar and some amount. In case of very low pressure, the compressor will not operate because it will be damaged.
The condenser inlet and outlet pressures will be the same as the compressor outlet. There will only be a temperature drop between the inlet and the outlet and the gaseous entering refrigerant liquid will exit.
In the expansion valve and the evaporator, the pressure drops to 1.0 bar and the temperature drops below 0 degrees. this decrease can be up to -10.

What are Vehicle Air Conditioning System Malfunctions? What are the solutions?

The air conditioning system may not cool the car from time to time for many reasons. If you say the air conditioning system does not cool, you are experiencing one or more of the following listed problems.

Failure Types

Lack or multiplicity of air conditioning gas

We have mentioned above the importance of the amount of gas in the air conditioning system. It is undesirable to have as much air conditioning gas as low. When the air conditioner gas is low in the system, the compressor will not produce enough pressure and the circulating gas in the system will not be able to fully fulfill its cooling feature. In order for the air conditioning system to operate at full performance, it must operate close to the above pressure and temperature values. Too much or too little air conditioning will cause them to drift away from these values ​​and reduce the performance of the system and even prevent it from operating.

Clogging in the moisture trap filter

We have explained the working principle and duty of the moisture trap filter above. Clogging in the moisture trap filter will slow the passage of the coolant and cause the pressure in the system to drop. In such a case, you can see that the moisture trap filter is cold when you hold it by hand. If the dehumidifier filter is cold, understand that it is clogged and needs to be replaced.

Decrease in compressor outlet pressure

The performance of the system will degrade as the refrigerant gas will not be sufficiently pressurized in the event that the compressor condition is reduced. In such a case, the A / C compressor must be maintained or replaced. The compressor must be in full condition so that the air conditioning system can work well.

Air conditioner radiator ie condenser pollution

Air conditioner radiator that prevents the cooling of the refrigerant gas in the condenser will prevent the operation of the system. In order for the system to work, the refrigerant gas entering the condenser must completely return to the liquid until the outlet. This is due to the fact that the condenser is clean so that condensation can occur and that there is no layer of pollution between the air from the air conditioning radiator fan and the radiator.

Distortion or wear of the expansion valve

The expansion valve, the backbone of the cooling system, needs to work well so that the whole system works well. Distortion or wear of the expansion valve will disrupt the pressure change balance by preventing it from performing its task fully. This will disrupt the operation of the air conditioning system.

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