Air Cooled Package Unit – Reliable, Efficient, and Ready-to-Install Cooling Solution

An Air Cooled Package Unit is an all-in-one HVAC solution that integrates the compressor, condenser, evaporator, and fan system into a single compact unit.

Designed for easy installation and efficient operation, these units are ideal for commercial and industrial applications such as shopping malls, factories, warehouses, offices, and other medium-to-large spaces.

Unlike split-type systems, the package unit does not require separate indoor and outdoor components. This makes it a convenient and cost-effective choice where space, installation time, and maintenance accessibility are major considerations.

Working Principle of an Air Cooled Package Unit

An Air Cooled Package Unit (PU) is a self-contained air conditioning system that performs the entire cooling process within a single outdoor-installed cabinet.

It includes the compressor, condenser, evaporator coil, expansion device, and air handling components, all integrated to deliver conditioned air directly into the building’s duct system.

1. Air Circulation and Return Air

The process begins when return air from the conditioned space is drawn into the package unit through the return air duct. This air passes through filters to remove dust and impurities before entering the evaporator section.

2. Evaporator Coil (Cooling Section)

The evaporator coil is responsible for absorbing heat from the return air. As the refrigerant passes through the evaporator coil, it evaporates from a low-pressure liquid into a gas, absorbing heat from the air in the process. The now-cooled air is then blown back into the building through the supply air ducts, cooling the indoor space.

3. Compressor (Heart of the System)

The compressor plays a vital role by sucking the low-pressure refrigerant vapor from the evaporator coil and compressing it into a high-pressure, high-temperature gas. This step is essential for maintaining the continuous flow of refrigerant throughout the system.

4. Condenser Coil (Heat Rejection Section)

The high-pressure gas then flows to the air-cooled condenser coil, where axial fans blow ambient air over the coil surface. The refrigerant releases its heat to the surrounding air, causing it to condense back into a high-pressure liquid.

Since it is air-cooled, the unit uses ambient air instead of water or cooling towers to reject heat—making it ideal for locations without a water source or where water usage must be minimized.

5. Expansion Device

After condensation, the refrigerant passes through an expansion valve or capillary tube, where its pressure and temperature drop significantly. This prepares the refrigerant to re-enter the evaporator coil, completing the refrigeration cycle.

6. Supply Air Distribution

Once the indoor air has been cooled (and dehumidified, if necessary), it is supplied through ductwork to various rooms or zones in the building. The cycle continues until the desired temperature set on the thermostat is reached.

Simplified Flow Summary

Return Air → Filter → Evaporator Coil (Cooling) → Compressor → Condenser Coil (Heat Rejection) → Expansion Valve → Evaporator Coil → Supply Air

Optional Features

Modern air-cooled package units may include:

·       Heating coils (electric or hot water type) for year-round operation

·       Economizer systems for fresh air cooling

·       BMS-compatible controls for remote monitoring and automation

Key Features

All-in-One Design

The system combines all major refrigeration and air handling components within a single enclosure, reducing piping and wiring work.

High Efficiency

Equipped with high-performance scroll compressors and aerodynamically designed condenser fans, the unit ensures maximum cooling capacity with low power consumption.

Durable Construction

The casing is made from electro-galvanized steel and finished with epoxy polyester powder coating to resist corrosion and weather conditions, making it suitable for outdoor installation.

Advanced Control Options

Available with microprocessor or intelligent control systems, allowing precise temperature management and compatibility with Building Management Systems (BMS).

Quiet Operation

The use of low-noise axial fans and optimized airflow design provides reliable cooling performance with minimal sound levels.

Easy Maintenance

All serviceable components are easily accessible from one side of the unit, reducing downtime and simplifying routine maintenance.

Applications

Air Cooled Package Units are suitable for:

• Commercial buildings (offices, malls, restaurants)

• Industrial facilities and factories

• Server rooms and data centers

• Hospitals and educational institutions

• Warehouses and workshops

Advantages of An Package Unit

• Simplified installation without the need for cooling towers or water piping

• Low maintenance cost and operational reliability

• Energy-efficient design reduces operating expenses

• Compact and flexible structure suitable for rooftop or ground-level installation

Conclusion

The Air Cooled Package Unit offers a complete, plug-and-play HVAC solution that delivers reliability, performance, and long-term energy savings. Its modular design, durable build, and flexible control options make it the preferred choice for modern commercial and industrial cooling applications.