Modular Indoor Central-Station Air-Handling Units

MasterFormat Division 23 73 13: Modular Indoor Central-Station Air-Handling Units

MasterFormat Division 23 73 13 covers modular indoor central-station air-handling units (AHUs). These units are essential components of many commercial and industrial HVAC systems, providing a centralized location for air treatment and distribution. Understanding their function, applications, and installation best practices are crucial for engineers, contractors, and building owners.

What is a Modular Indoor Central-Station Air-Handling Unit?

A modular indoor central-station AHU is a pre-engineered and factory-assembled HVAC unit designed for indoor installation. It consists of multiple modules or sections containing various components, such as:

• Supply and return air fans
• Heating and cooling coils
• Air filters
• Humidifiers or dehumidifiers
• Controls and dampers

These modules are shipped to the job site and assembled to form a complete AHU, offering flexibility in configuration and installation.

How Does a Modular Indoor Central-Station AHU Work?

Modular indoor central-station AHUs condition and circulate air throughout a building using the following process:

1. Air Intake: The AHU draws in return air from the building through a return air duct.
2. Filtration: The air passes through filters to remove dust, pollen, and other contaminants.
3. Heating or Cooling: The air is then heated or cooled as needed by passing over coils containing hot water, steam, refrigerant, or chilled water.
4. Humidity Control: The unit may also adjust the humidity levels by adding or removing moisture from the air.
5. Air Distribution: Finally, the conditioned air is distributed to various zones within the building through a network of supply air ducts.

Where Are Modular Indoor Central-Station AHUs Commonly Used?

Modular indoor central-station AHUs are widely used in various commercial and industrial settings, including:

• Office buildings
• Hospitals
• Schools and universities
• Shopping malls
• Hotels
• Manufacturing facilities

These units are suitable for applications requiring high airflow rates, precise temperature and humidity control, and energy efficiency.

Installation Best Practices for Modular Indoor Central-Station AHUs

Proper installation is essential for optimal performance and longevity of modular indoor central-station AHUs. Key best practices include:

• Site Accessibility: Ensure adequate space and access for transporting and assembling the modules.
• Leveling and Support: Install the AHU on a level platform with sufficient structural support.
• Ductwork Connections: Seal all ductwork connections carefully to prevent air leaks.
• Electrical Connections: Follow all electrical codes and guidelines during wiring.
• Control System Integration: Integrate the AHU's control system with the building management system (BMS) for centralized monitoring and control.
• Commissioning: Have a qualified technician commission the unit after installation to ensure proper operation and performance.

Top Manufacturers of Modular Indoor Central-Station AHUs

Several reputable manufacturers specialize in producing modular indoor central-station AHUs, including:

• Carrier
• Trane
• York
• Daikin
• Lennox
• McQuay

Conclusion

Modular indoor central-station AHUs play a vital role in maintaining comfortable and healthy indoor environments. By understanding their functionality, applications, installation best practices, and leading manufacturers, you can make informed decisions regarding your HVAC system design, procurement, and maintenance. Consult with experienced HVAC professionals to determine the most suitable AHU solution for your specific needs.