Introduction
The AAON M2 Series air handling units provide an exceptional solution for new installations and replacement projects. Featuring an innovative modular design and premier factory-installed features, these units prioritize serviceability and ease of maintenance. They are known for remarkable quietness, unwavering reliability, superior energy efficiency, and robust construction, making them ideal for diverse project requirements.
For M2 Series modular units, AAON sets a new standard for excellence in modularity, performance, serviceability, and long-term value, covering capacities from 3,800 to 21,000 cfm.
Standard Features
- Available as a chilled water or non-compressorized DX air handling unit
- Water-source and geothermal heat pump options
- Electric, steam, or hot water heating design for application flexibility
- Direct drive backward curved plenum fans
- Double wall rigid polyurethane foam panel construction with a minimum R-16 value
- Access doors with removable pin hinges, lockable zinc cast handles, and slide-out access to coils and energy recovery wheels for easy maintenance and cleaning
- AMCA certified and labeled low leakage economizer dampers utilize outdoor air for cooling under certain conditions
- Power exhaust and power return options with economizer
- Double-sloped stainless steel drain pans for effective drainage and prevention of standing water
- Run test report, wiring diagram, and Installation, Operation, and Maintenance (IOM) manual provided with every unit
Direct Drive Backward Curved Plenum Fans offer greater energy efficiency, quieter operation, and require less maintenance than belt-driven fans. VFD controlled and ECM driven supply, exhaust, and return fans are available for precise airflow control, building pressure control, and reduced power consumption.
Construction and Serviceability
Durable, Energy-Efficient Design
Features double wall construction with closed-cell polyurethane foam insulation and G90 galvanized steel walls. This design provides an insulation R-value of 16 (2-inch construction) and R-8 (1-inch construction), enhancing rigidity, durability, and significantly reducing unwanted heat transfer. It avoids fiberglass insulation, which can be harmful to indoor air quality.
Streamlined Serviceability
AAON equipment is designed for efficient serviceability, reducing downtime and costs. Accessible control components, color-coded wiring diagrams, and labeled components minimize diagnostic time. This feature ensures low service costs and maximizes unit run time.
Accessible Cabinet Doors
Access doors feature removable pin hinges and lockable zinc cast handles, allowing for easy serviceability for maintenance and troubleshooting.
Increased Thermal Resistance
The double wall rigid polyurethane foam insulated cabinet panel increases thermal resistance, reduces air leakage, and attenuates radiated sound. A thermal break minimizes heat transfer between interior and exterior metal cabinet walls.
Illustration shows a double layer configuration with a thermal break between interior and exterior metal cabinet walls.
Configurability
Variable Capacity Technology
A single zone VAV system utilizes variable capacity compressor technology and modulating VFD controlled supply fans to accurately control cooling and humidity levels, ideal for applications with varying sensible and latent loads.
Enhanced Airflow and Air Quality
Units can be equipped with makeup air capabilities and low leakage AAON economizers for up to 100% outside air. Modulating reheat can be added for accurate humidity control.
Low Energy Consumption and Leakage
Factory-installed, sensible or enthalpy, gear-driven economizers provide free cooling and eliminate the play and bind found in linkage types. Standard AMCA certified, low leakage dampers meet California Title 24 requirements.
Precise Humidity Control
Modulating hot gas reheat systems efficiently deliver precise reheat for optimal space comfort and dehumidification, avoiding the abrupt temperature fluctuations associated with on/off reheat systems.
Configurable Air Handling
AAON M2 Series air handling unit modules offer practical design flexibility to meet various job application requirements. They are engineered to accommodate specific spatial constraints, performance criteria, or energy efficiency goals. Their modular construction simplifies customization and potential future expansions.
Illustration shows a single layer configuration.
Options
- Hot water or steam heating coils for integration with existing boiler systems
- Chilled water cooling coils for integration with existing chilled water systems
- VFD controlled or ECM driven backward curved plenum supply fans for precise airflow and reduced power consumption
- Modulating Hot Gas Reheat for precise humidity control and consistent occupant comfort
- Multiple high efficiency air filtration options (e.g., MERV 13+) for improved indoor air quality
- Factory installed AAONAIRE® total and sensible energy recovery wheels for pre-conditioning air and reducing heating/cooling loads
- SCR (Silicon Controlled Rectifier) electric heat control for reduced power consumption and improved occupant comfort
- Polymer e-coated coils for enhanced corrosion protection
- Power exhaust options for improved indoor air quality
- Return and supply side firestat options for additional safety
- Phase and Brownout protection against voltage imbalance
- Controls section service lights for easier maintenance
- Shrink wrap and export crating available for protective shipping
- Different paint color options available for unit customization
- Additional customization available upon request
Low GWP Refrigerant
Global Warming Potential (GWP) measures a refrigerant's heat-trapping capacity. AAON equipment now uses R-454B, a next-generation refrigerant with a GWP of 466, which is significantly lower than traditional refrigerants. R-454B offers high performance and reliability, similar to R-410A, facilitating an easy transition. AAON's selection of R-454B supports the industry's move towards cleaner and more sustainable HVAC systems.
Heat Pumps
The M2 Series offers efficient cooling and heating capabilities via its heat pump option, which reverses refrigeration circuits to provide heating without the need for gas or electric heat, thereby eliminating fossil fuel usage. This can lead to potential cost savings compared to gas heating systems. The M2 is available as a water-source or geothermal heat pump.
Geothermal Heat Pump
Geothermal heat pumps utilize underground pipes and water flow to transfer heat between the building and the earth, leveraging stable ground temperatures (45°F to 75°F) for efficient heating in winter and cooling in summer. Ground water heat pumps use bodies of water for heat transfer.
Water-Source Heat Pump
Water-source heat pumps operate similarly to geothermal units but utilize a cooling tower and boiler system. They are commonly applied in multistory buildings or large campuses.
Indoor Air Quality
The quality of air inside a building significantly impacts occupant health and cognition. AAON's standard design and rooftop equipment options enhance indoor air quality.
Construction
Features a cleanable metal liner in the cabinet interior. The M2 Series uses foam-insulated panels instead of fiberglass, preventing dirt or moisture trapping. This composite panel construction ensures low air leakage and minimizes unconditioned air infiltration.
AAONAIRE® Energy Recovery Wheel
Sensible or enthalpy energy recovery wheels pre-condition outside air, significantly improving energy savings and reducing unit operation costs, especially for makeup air units. Wheels are available in polymer or aluminum construction with removable segments for easy cleaning.
Polymer E-Coated Coils
An immersion process applies a consistent, thick polymer coating to coils, minimizing coverage gaps. This coating provides over 6,000 hours of corrosion protection in salt spray testing and preserves coil thermal performance for durability and reliability.
Filtration
ASHRAE recommends a minimum of MERV 13 filters for effective virus trapping. Options include pleated or cartridge filters with up to 95% efficiency (MERV 14), installable as prefilters, final filters, or a combination.
Stainless Steel Drain Pans
Fabricated from stainless steel, these drain pans ensure positive drainage and offer superior corrosion resistance for long-lasting durability.
Precision Cooling and Heating Control
M2 Series units offer two-step or variable capacity compressors, depending on cabinet size and application. Modulating compressors ensure precise cooling control, while SCR-controlled electric heat provides precise heating temperature control.
Two-Step Compressors
Allow for improved part load efficiency with simple staged control on select M2 units, optimizing IEER without complex controls, thereby reducing operating costs and maintenance.
Precision Heating Control
SCR-controlled electric heat strips offer optimal precision heating. Flexible heating solutions, including hot water coils, integrate seamlessly with existing boiler systems.
Variable Capacity (Digital) Compressors
Provide a wide range of capacity control (10-100%) for improved part load efficiency with simple controls.
Specifications
M2 Series Air Handling
| Capacity | 3,800 - 21,000 cfm |
|---|---|
| Configuration | Horizontal |
| Nominal cfm | M2-018: 6,000 cfm M2-026: 13,500 cfm M2-036: 18,500 cfm |
| Dimensions* (inches) | M2-018: 84 W x 48 H(SL) x 98 H(DL) M2-026: 84 W x 64 H(SL) x 128 H(DL) M2-036: 96 W x 70 H(SL) x 142 H(DL) |
*Dimensions vary depending on options selected. Design cfm may be 30-50% greater or less than nominal cfm. (SL) = Single Level, (DL) = Dual Level.
M2 Series Water-Source Heat Pump
| Capacity | 16-60 tons |
|---|---|
| Configuration | Horizontal |
| Model Number | M2-018: 16, 18, 20, 25, and 30 tons M2-026: 30, 40, and 50 tons M2-036: 50 and 60 tons |
| Dimensions* (inches) | M2-018: 84 W x 48 H(SL) x 98 H(DL) M2-026: 84 W x 64 H(SL) x 128 H(DL) M2-036: 96 W x 70 H(SL) x 142 H(DL) |
*Dimensions vary depending on options selected. (SL) = Single Level, (DL) = Dual Level.
The M2 provides a fully custom solution with configurable boxes that can be assembled into modular air handling units for split-system applications or self-contained water-source heat pump units. Matching air-cooled condensing units are available for complete split system solutions ranging from 13 to 60 tons.
Quality and Support
Built to last. Built for you.
There is confidence in choosing AAON. Efficient operations ensure premier AAON quality at a reasonable price. Outstanding serviceability and support create lifetime AAON customers.
Find Your Representative
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AAON is always innovating. For the latest information, visit aaon.com or talk to your AAON representative.
Document Revision: Rev. 250919
