Custom Indoor AHU

Custom solutions for large and hyperscale data centers

To Contact Form

Customized. Efficient. Reliable.

Breaking new ground: When it comes to large and hyperscale data centers, conventional air conditioning systems are up against their limits. Restricted space, electricity consumption and high heat loads are some of the challenges that need to be overcome. STULZ offers solutions to these challenges and guarantees efficient, demand-based and reliable air conditioning of your mission-critical equipment.

Our custom air handling units unique design allows space for taller server racks with greater IT load densities, therefore enabling air conditioning of the maximum heat load.

Optimized for air conditioning particularly large data centers
Data Center
Data Center
Our units are designed for highest requirements and maximum reliability
Customizable down to the last detail
Small, medium & large rooms
Small, medium & large rooms
Precision air conditioning units for low to high heat loads
Grow with your requirements

Product Overview

At a glance


  • Large and hyper scale data centers
  • Free Cooling 
  • IT Sector


  • Does not need raised flooring
  • Indoor installation
  • Low pPUE values
  • Lowest AER ( Airflow Efficiency Ratio ) Values and therefore conduction with maximum efficiency
  • Supply Air temperature within the range recommended by ASHRAE TC 9.9 guidelines
  • Best price-performance ratio
  • Compact footprint yet maximized cooling capacity


  • Low pPUE values
  • Best price-performance ratio
  • Taller racks and higher heat loads possible because no raised floor is needed
  • Supply air temperature within the range recommended by ASHRAE TC 9.9 guidelines
  • lowest AER ( Airflow Efficiency Ratio )  values and therefore conduction with maximum efficiency
  • Use of EC technology for maximum efficiency

Design Concept:

  • Compact footprint yet maximized cooling capacity
  • Higher efficiency and lower noise level
  • Robust, extruded aluminum construction with various panel thicknesses, including a thermal break option
  • Zero size clearance, space-efficient, modular design
  • Operational reliability and redundancy through modularity
  • Provides uniform cooling along the entire length of the aisle due to the larger are of supply air




  • All parts requiring maintenance can be accessed from the front
  • Quick installation
  • Factory trained and experienced sales and service partners in over 140 countries
  • Lowest total cost of ownership (TCO)
  • Robust construction with aluminum frame
Technical Data

USA - 

Technical DataCAH-0100CAH-0200

Cooling Capacity (kW)

Airflow (ft^3/min)12,50025,000
Weight (lbs)2,8005,600
Dimensions (in)59.1x94.5x61.4118.1x94.5x61.4

Custom AHU Details

Customized Modular Design for Maximum Cooling Density


STULZ offers an extensive range of cooling capacities and systems, along with various unit configurations, designed to create the optimum solution for your individual requirements. With the STULZ Custom Indoor AHU, our customers receive a purpose-built solution that has been ideally configured for their application.



Horizontal AHU

The horizontal AHU, available with direct expansion (DX) and chilled water (CW) cooling,  is designed specifically to meet customer requirements.  A specialized fan wall array ensures uniform airflow while meeting low power consumption requirements.  Counterbalanced fan inlet backdraft dampers minimize air recirculation. 

Modular Split AHU

The modular split AHU is available with DX and CW cooling. A vertical center split allows the modular AHU to fit in service elevators and maneuver within tight spaces.  Its modular design allows easy reassembly and rewiring on-site using minimal labor (via frame and electrical connectors).  The unit can also be deployed and/or operated as a half unit by only utilizing one side, therefore increasing redundancy.


Horizontal Stackable Fan/Coil Unit

Stackable chilled water fan coil unit reduces total footprint while maintaining unit serviceability.  Designed to easily stack units securely.  Electrical connectors provided between stacked units to reduce on-site installation time and cost.

Horizontal Split Sectional AHU

The horizontal split sectional AHU is available with DX and CW cooling.  It is sized and split to fit in a standard freight shipping container for intermodal transportation.  Unit can be easily reassembled and rewired on site using minimal labor (via frame and electrical connectors).  Air discharge sound attenuators provided for low sound applications.


STULZ Custom Indoor Horizontal Split Sectional AHU


The WallFlow horizontal AHU is based on a highly successful custom design that is deployed in multiple locations. Its standardized design enables shorter delivery times while still offering various options or individual customization.

Features & Benefits:

  • Modular solution - stackable & expandable
  • Compact footprint with maximized cooling capacity
  • Robust construction with aluminum frame
  • Zero clearance installation
  • Larger supply/return area
  • Customization through various design options and cooling systems: Direct Expansion, Chilled Water, and Direct Adiabatic
  • Horizontal and vertical supply and return configurations
EC Fans

EC Fans

  • Speed-controlled fan
  • Nominal airflow rate at a fan speed optimized for partial load
  • UPS available for continuous fan operation
  • Multiple fan sizes available
  • Increased airflow in each size



Fold-out fans for quick and easy maintenance and easily removable filters to ensure quick filter replacement.


PICV/Energy Valve

  • Dynamic load balance across all operating conditions
  • Eliminates problems associated with low delta T syndrome
  • Precisely matches design requirements for capacity and delta T
  • Maximizes energy savings of variable flow systems while addressing unique control challenges
STULZ E² Control and Monitoring

STULZ E² Control and Monitoring

  • Designed specifically for precision control of mission critical environments
  • Multiple I/O capabilities for all major components to optimize control for energy savings
  • Supports universal BMS interface for remote monitoring (address readable) and remote control (address writable)
  • Capable of network controllers in a workgroup (pLAN) to work as one (no BMS required)
  • Pre-engineered controls for economizers and adiabatic cooling

STULZ E² Benefits

  • Backlit LCD alphanumeric display for visual indication
  • Operated via 6-key menus, in five different modes
  • Unit functions for cooling, heating, humidifying and dehumidifying
  • Three levels of restricted entry into the configuration
  • Sensor inputs control inputs/outputs
  • Additional I/O sensors and alarms
  • Optionals UPS backup module 
  • Independent EC Fan and cooling control (CW valve or DX)
  • Cooling control sequence: return air temperature, humidity, supply air temperature, dew point
  • Fan control sequence: BMS, local/static pressure, and temperature based (supply or return air)
  • Capable of networking up to eight EControllers with an independent LAN
  • Psychrometric control provided as a user configurable temperature and humidity (relative humidity) or dew point control

STULZ E² Controller communicates with BMS/BAS systems via the following protocols:

  • BACnet IP
  • BACnet over Ethernet
  • BACnet MS/TP
  • HTTP
  • SNMP V1, V2c
  • Modbus IP
  • Modbus RTU


Find your individual STULZ contact

Need more information?

Download Technical Documents Here!
  • File:
  • Language:
  • Date:

Related Products

CyberAir® CW and DX

Learn More


Learn More

Compact CWE

Learn More


Do you have any questions? We will be happy to help! Please call us or follow our contact form.

To Contact Form
To top