How does parking air conditioning work?

‌Compression stage‌
The electric-driven compressor compresses the gaseous refrigerant into high-temperature and high-pressure gas

Compared with traditional idling air conditioners, electric compression reduces engine wear and carbon deposit risks

‌Condensation and heat dissipation‌
The high-temperature refrigerant enters the condenser and is forced to cool by the cooling fan and converted into a medium-temperature and high-pressure liquid

Heavy-duty trucks mostly use a top-mounted condenser design to enhance heat dissipation efficiency by using the driving wind

‌Throttling and pressure reduction‌
The liquid refrigerant is reduced in pressure by the expansion valve and becomes a low-temperature and low-pressure mist mixture8

‌Evaporation and heat absorption‌
The refrigerant absorbs the heat in the cab in the evaporator to achieve air cooling (as low as 18°C)

The core of any truck parking air conditioner is its closed-loop refrigeration system. This system uses a refrigerant—a chemical fluid that can change from gas to liquid and back again. The cycle starts with the compressor, which compresses the refrigerant gas, increasing its pressure and temperature.

Next, the hot gas travels to the condenser, often mounted outside the cabin. Here, the gas cools down and condenses into a high-pressure liquid as it releases heat into the outside air. A fan helps with this cooling process by pushing air over the condenser coils.

The liquid refrigerant then moves through an expansion valve, where it experiences a pressure drop. This sudden drop causes the refrigerant to cool significantly and partially evaporate. It then enters the evaporator coil located inside the cabin.

As the refrigerant absorbs heat from the cabin air, it evaporates into a gas again, cooling the surrounding air. A blower fan distributes this cooled air throughout the truck cabin. The gas then returns to the compressor, and the cycle continues.

This entire process is powered by a battery or auxiliary power unit (APU), making it independent of the truck's engine. Modern truck parking air conditioners are designed to run efficiently for hours, helping drivers rest comfortably while meeting anti-idling regulations and reducing fuel consumption.

In hot weather, having a reliable cooling system while your vehicle is parked can make a big difference in comfort. This is where AC car parking coolers come in. These systems are designed to keep the vehicle interior cool while the engine is off, making them especially useful for long breaks, outdoor work, or overnight stays in vehicles. So, what features make AC car parking coolers effective and convenient?

One of the important features is engine-off operation. Unlike traditional air conditioning systems that rely on the car engine, AC car parking coolers are designed to run independently—usually powered by the vehicle's battery or an external power supply. This reduces fuel usage and complies with anti-idling laws in many regions.

Another valuable feature is low power consumption. These units are built to use minimal energy while still providing effective cooling. Many models come with energy-saving modes, which adjust the compressor and fan speed based on the cabin temperature, ensuring efficient use of power and extended operation.

Portability and ease of installation are also significant. Many AC car parking coolers are compact, lightweight, and designed for easy installation on the roof or in the rear window area. Some are portable and can be transferred between vehicles, which is useful for fleet owners or those with multiple cars.

Users will also find digital control systems a helpful feature. These allow you to set the desired temperature, timer functions, and even remote operation. Some models also include LCD displays or smartphone app compatibility, making operation more user-friendly.

Quiet performance is another plus. Many modern AC car parking coolers are designed to operate at low noise levels, making them suitable for rest periods or overnight use without disturbing sleep.

Together, these features make AC car parking coolers a practical choice for improving vehicle comfort without relying on engine power. Whether for personal use or commercial vehicles, they offer a smart balance of convenience, energy efficiency, and reliable cooling.