Selecting the right Air Handling Unit (AHU) requires a comprehensive evaluation of key parameters and application needs. Understanding these factors will help ensure optimal performance, energy efficiency, and cost-effectiveness. Below is a detailed explanation of the core parameters to consider when choosing an AHU model.
1. Airflow (m³/h)
- Definition: Airflow refers to the volume of air passing through the AHU per unit time, usually measured in cubic meters per hour (m³/h).
- Selection Criteria:
- Based on room size and ventilation rate.
- Varies between comfort air conditioning and industrial cleanroom applications.
2. Temperature & Humidity Control
- Definition: Determines the AHU’s ability to regulate indoor temperature and humidity levels.
- Selection Criteria:
- Industrial and pharmaceutical environments often require precise control.
- Choose an AHU model with appropriate heating, cooling, humidification, or dehumidification functions.
3. Cleanliness Class (Air Purification Level)
- Definition: Specifies the filtration and purification capabilities of the AHU, critical in cleanrooms, hospitals, and pharmaceutical production.
- Selection Criteria:
- Adherence to ISO cleanroom classifications or GMP (Good Manufacturing Practice) standards.
- Choose multi-stage filtration (e.g., HEPA, ULPA) for high-purity applications.
4. Pressure Control
- Definition: Ensures balanced airflow and pressure levels within the system.
- Selection Criteria:
- Positive pressure for sterile environments (e.g., operating rooms, pharmaceutical labs).
- Negative pressure for contaminant control (e.g., isolation wards, hazardous material labs).
5. Functional Segments
AHUs consist of various functional sections, which should be configured based on specific application needs:
- Filtration Segment – Select filter grades (G4, F7, H13, H14) based on air quality requirements.
- Cooling/Heating Segment – Choose chilled water coils, DX coils, or electric heaters depending on climate conditions.
- Humidification/Dehumidification – Necessary for precise humidity regulation in sensitive environments.
- Fan Section – Select between centrifugal fans, EC fans, or direct-drive systems based on airflow and static pressure needs.
6. Energy Efficiency
- Definition: Determines operational cost and environmental impact.
- Selection Criteria:
- Opt for EC (Electronically Commutated) fans for high efficiency.
- Use heat recovery systems to reduce energy consumption.
- Consider variable speed drives (VSD) for fan motors to optimize performance.
7. Control System
- Definition: Enables monitoring and automation for optimized performance.
- Selection Criteria:
- Smart control systems with remote monitoring capabilities.
- Integration with Building Management Systems (BMS) for centralized control.
8. Installation Space & Maintenance
- Definition: Ensures the AHU fits within available space and allows for easy servicing.
- Selection Criteria:
- Evaluate dimensions to ensure compatibility with mechanical rooms or rooftop installations.
- Choose modular designs for easier maintenance and upgrades.
9. Noise Level
- Definition: Important in environments with strict noise control requirements (e.g., hospitals, hotels, office spaces).
- Selection Criteria:
- Opt for low-noise fan motors.
- Use soundproofing materials or silencers if necessary.
10. Budget & Brand Reputation
- Definition: Balances performance, cost, and long-term value.
- Selection Criteria:
- Compare total cost of ownership (TCO), not just initial purchase price.
- Choose reliable brands with strong warranty and after-sales support.
Conclusion
Choosing the right AHU model involves evaluating airflow, temperature control, cleanliness requirements, pressure regulation, energy efficiency, and maintenance needs. Consulting with HVAC professionals or manufacturers will ensure that your AHU selection aligns with both current and future operational demands.
How to Choose the Right AHU Model: Parameter Analysis