Air-Cooled Precision Air Conditioning (PAC) Units for IT Rooms and Data Centers

Air-cooled precision units, also referred to as Precision Air Conditioning (PAC) or Computer Room Air Conditioning (CRAC) units, are specifically engineered to maintain stable environmental conditions in IT rooms, server rooms, and small to medium-sized data centers. Unlike comfort air conditioning, precision units provide continuous, 24/7 operation with tight control over temperature, humidity, and airflow—critical factors for protecting sensitive IT equipment and ensuring system availability.

Why Air-Cooled Precision Units for IT Rooms

Air-cooled precision units are widely adopted in IT rooms due to their independent operation, ease of installation, and high reliability. They do not require cooling towers or chilled water infrastructure, making them ideal for retrofit projects, edge data centers, and distributed IT facilities.

Key benefits include:

• Accurate Temperature Control
  Typically ±1°C control to prevent overheating and thermal cycling of IT equipment.

• Reliable 24/7 Operation
  Designed for continuous duty with redundant components and high-quality compressors.

• Optimized Airflow Management
  High sensible heat ratio (SHR) ensures effective removal of server heat loads.

• Compact and Modular Design
  Suitable for space-constrained IT rooms and scalable expansion.

• Low Maintenance Requirements
  Air-cooled condensers simplify operation and reduce water-related maintenance risks.

Typical Applications

• Server rooms and IT rooms in commercial buildings

• Edge data centers and telecom rooms

• Network operation centers (NOC)

• Financial institutions and control rooms

• Industrial automation and SCADA rooms

Case Study: Air-Cooled Precision Units for a Financial Institution IT Room

Project Background

A regional financial institution required an upgrade to the cooling system of its primary IT room supporting core banking applications. The existing comfort air conditioning system was unable to maintain stable temperatures under increasing server density, resulting in frequent high-temperature alarms and operational risk.

Challenges

• High sensible heat load from densely packed server racks

• Requirement for 24/7 uninterrupted operation

• Limited space for outdoor equipment

• Need for rapid deployment with minimal downtime

Solution Provided

Two air-cooled precision units were installed in an N+1 configuration to ensure redundancy. Each unit was designed for continuous operation with the following features:

• High-efficiency air-cooled condensers installed on the rooftop

• EC fans for variable airflow and improved energy efficiency

• Microprocessor-based controller with temperature and humidity monitoring

• Compatibility with the building management system (BMS)

Cold air was supplied through a raised floor, ensuring uniform airflow distribution across all server racks.

Results

• Stable Temperature Control: IT room temperature maintained at 24°C ±1°C

• Improved Reliability: Elimination of temperature-related alarms and shutdown risks

• Energy Optimization: Reduced energy consumption compared to the previous comfort AC system

• Operational Continuity: Zero unplanned downtime since commissioning

The air-cooled precision units provided a robust and scalable cooling solution aligned with the institution’s IT growth and reliability requirements.

Conclusion

Air-cooled precision units are a proven solution for IT rooms requiring reliable, accurate, and continuous cooling. Their ease of installation, strong performance under high sensible heat loads, and suitability for redundancy configurations make them an ideal choice for mission-critical IT environments. With proper system design and control integration, air-cooled precision units significantly enhance equipment protection and overall IT infrastructure resilience.