How does car AC system work

Summary

The script explains how air conditioning systems maintain a comfortable environment in vehicles, enhancing driver focus and road safety. It details the refrigerant cycle involving components like the compressor, condenser, expansion valve, and evaporator. The transition to R1234yF refrigerant for environmental reasons is noted. The process includes heat absorption, compression, condensation, expansion, and evaporation, with a pressure sensor as a safety feature to prevent system damage.

Takeaways

• ❄️ Air conditioning systems maintain a comfortable temperature and humidity inside the passenger compartment, improving driver focus and road safety.
• 🌡️ The system works by removing heat from the cabin, using a refrigerant to absorb and release heat to the outside air.
• 🛠️ Main components of an air conditioning system include the compressor, condenser, expansion valve, evaporator, and refrigerant (R134a or R1234yf).
• ⚙️ The compressor, typically driven by the engine, circulates refrigerant through the system. In electric and hybrid vehicles, electric motors drive the compressor.
• 🌀 The refrigerant cycle starts with the compressor, where gaseous refrigerant is compressed and heated, then sent to the condenser to release heat.
• 💧 The condenser cools the refrigerant, causing it to change from a gas to a liquid. It has sections for removing heat, condensing, separating gas from liquid, and sub-cooling.
• 🔄 The cooled liquid refrigerant flows to the expansion valve, where pressure is reduced, turning it into a cooler mist that absorbs heat more efficiently.
• 🌬️ The mist refrigerant passes through the evaporator, where it absorbs heat from the cabin air and changes back into a gas, completing the refrigerant cycle.
• 📉 The expansion valve regulates the flow of refrigerant to ensure the right amount of heat is absorbed in the evaporator.
• ⚠️ A pressure sensor in the system monitors refrigerant pressure and can deactivate the compressor to prevent damage if the pressure is abnormal.

Q & A

What is the primary purpose of an air conditioning system in a vehicle?

The primary purpose of an air conditioning system in a vehicle is to create a comfortable temperature and humidity inside the passenger compartment, which helps the driver and passengers feel relaxed and enhances the driver's concentration, leading to increased road safety.

How does the air conditioning system cool the passenger compartment?

The air conditioning system cools the passenger compartment by absorbing heat into a refrigerant, which then transports the heat away from the compartment and releases it to the outside air.

What are the main components of an air conditioning system?

The main components of an air conditioning system are the compressor, condenser, expansion valve, evaporator, and the refrigerant.

What refrigerants are commonly used in air conditioning systems?

Most air conditioning systems use R134a as the refrigerant. However, since January 2017, new car air conditioning systems are required to use R1234yf for environmental reasons.

How is the compressor powered in different types of vehicles?

In traditional vehicles, the compressor is driven by the engine using a drive belt and a magnetic clutch. In some systems, a dual pulley continuously drives a variable displacement compressor. In electric and hybrid vehicles, the compressor is powered by an electric motor.

What role does the compressor play in the air conditioning system?

The compressor creates the flow of refrigerant through the air conditioning system by compressing the refrigerant gas, creating high pressure at the discharge port and low pressure at the suction port.

What is the function of the condenser in an air conditioning system?

The condenser transfers heat from the refrigerant to the outside air. It consists of four sections: the gaseous section, condensing section, gas-liquid separator, and sub-cooling section, which work together to release heat and change the refrigerant from gas to liquid.

How does the expansion valve contribute to the cooling process?

The expansion valve reduces the pressure of the refrigerant by forcing it through a small orifice, turning it into a mist. This reduces the temperature, allowing the refrigerant to absorb heat more efficiently when it passes through the evaporator.

What happens to the refrigerant in the evaporator?

In the evaporator, the refrigerant absorbs heat from the passenger compartment air. This heat causes the refrigerant to change from a low-pressure mist back into a gas, which is then sent back to the compressor.

What is the function of the pressure sensor in an air conditioning system?

The pressure sensor monitors the refrigerant pressure on the high-pressure side between the condenser and the expansion valve. If the pressure is incorrect, which could cause damage to system components, the compressor can be switched off as a safety measure.