CRAC Units, CRAH Units and Fan Walls for Data Centers
Scalable air cooling solutions for data centers, from precision CRAC and CRAH units to high-capacity modular fan walls. Explore solutions designed to deliver efficient, reliable cooling across a wide range of data center environments.
Data Center Air Cooling for Every Scale
Munters combines precision CRAC and CRAH units with scalable fan wall systems to support traditional, hyperscale and high-density data centers. The portfolio enables efficient airflow management, redundancy and flexible cooling capacity across the data hall.
A Complete Cooling Ecosystem
Designed as part of an integrated cooling architecture, our CRAH, CRAC, and fan wall systems support scalable, hybrid, and AI-ready data center deployments.
Airflow systems are a key part of complete data center cooling systems, helping balance room-level stability with facility cooling, liquid loops and heat rejection.
- Air- and water-cooled chillers
- Dry coolers and free-cooling systems
- Elevated-temperature liquid loop architectures
- CDUs and direct-to-chip liquid cooling
- Precision EDPAC (CRAC/CRAH) and MCW (Fan Wall) systems
- Controls, monitoring, and lifecycle support
CRAC and CRAH Units for Data Centers
CRAC and CRAH units provide precision air cooling and temperature control for data center environments. Munters EDPAC systems offer compact, scalable cooling for both new data center construction and retrofit applications.
CRAC units use direct-expansion refrigeration, while CRAH units use chilled water supplied by the facility cooling system. The right configuration depends on cooling architecture, capacity requirements and available infrastructure.
When to Use Fan Wall Architectures
As AI rack densities rise and liquid cooling becomes standard at rack level, maintaining stable and uniform room-level airflow becomes critical. Fan walls, modular arrays of EC fans, distribute airflow evenly across the data hall, reducing hotspots and enabling precise control. Data center operators deploy fan walls to achieve:
- Uniform airflow across the entire white space
- Improved thermal stability at higher rack densities
- Built-in redundancy through multi-fan arrays (N+1, N+2)
- Modular scalability without large single-point failures
- Lower fan energy through EC fan technology
- Greater flexibility in room layout and airflow design
- Stable room-level airflow in halls with 80-150 + kW AI racks
Modular ChilledWall (MCW)
Munters Modular Chilled Walls (MCW) solutions apply fan wall principles within a fully engineered cooling module, delivering predictable airflow, efficient heat removal and system-level reliability.
MCW is one implementation of fan wall architecture within the Munters portfolio, frequently used in high-density and AI-ready data halls. They integrate:
- EC fan arrays
- Chilled-water cooling coils
- Controls and monitoring
- Modular mechanical design
CRAH, CRAC and Fan Walls in Hybrid Air and Liquid Cooling
In modern AI facilities, liquid cooling handles high-density GPU racks, while air systems manage residual loads, networking, storage and room-level stability. Fan walls provide the distributed airflow backbone in these hybrid architectures.
In facilities using elevated-temperature or warm-water liquid loops to maximize free cooling, maintaining stable room airflow is essential to prevent localized overheating and recirculation.
Common hybrid use cases include:
Liquid cooling for high-density or AI racks
Fan wall-based air cooling for surrounding white space
CRAH or fan wall systems supporting residual heat loads
Gradual migration from air cooling to liquid cooling
Engineering-Led Airflow Design for Mission-Critical Data Centers
System-level airflow engineering ensures predictable thermal performance across varying rack densities. Whether integrating traditional EDPAC CRAC/CRAH units or deploying a Modular ChilledWall (MCW) architecture, Munters supports data center projects with:
- Airflow and pressure modeling
- Fan wall sizing and redundancy analysis
- Hot- and cold-aisle optimization
- Integration with chiller and liquid cooling systems
- Retrofit assessments for existing facilities
- Rapidly rising TDP for next generation GPUs and accelerators
- Airflow validation in mixed-density AI zones with liquid-cooled racks
- Grid constraints and limited power availability at scale
Related Air Cooling Approaches
Our CRAH, CRAC and fan wall units are part of a broader set of air-based cooling technologies used in data centers.
- Rear-door heat exchangers (air-based) for rack-level heat capture
- Top-of-rack air delivery, used in specific cabinet-level designs
- Fan coil walls (coil-based terminal cooling modules)
Service and Support for Mission-Critical Uptime
As the original equipment manufacturer, Munters designs, builds, and services data center cooling systems – ensuring uptime, performance, and long-term reliability.
Our engineering-led service approach supports system performance and reliability across the full lifecycle, from commissioning to optimization and upgrades.
- Commissioning and validation
- Preventive and predictive maintenance
- Access to genuine OEM spare parts
- System upgrades and retrofit solutions
FAQ – CRAH and Fan Walls for Data Centers
A CRAC (Computer Room Air Conditioner) unit uses a self-contained compressor and refrigerant (DX), making it ideal for facilities without a central chiller. A CRAH (Computer Room Air Handler) unit uses chilled water from an external source, offering higher energy efficiency for larger-scale data centers.
Traditional CRAHs are excellent for moderate densities in raised-floor environments. However, fan walls like the MCW are superior for high-density or AI-ready halls where uniform, high-capacity airflow and fan-level redundancy are critical for stability.
Yes. We offer the EDPAC range for precision CRAC and CRAH requirements, and the Modular ChilledWall (MCW) for facilities seeking the benefits of advanced fan wall architectures.
Yes. While liquid cooling removes heat at rack level, stable and uniform room-level airflow remains essential for residual heat loads, network equipment and overall thermal balance. Fan walls are commonly deployed in hybrid AI facilities.
Yes. Their modular nature makes them well-suited for phased upgrades and density increases in existing data centers.
Ready to design your airflow architecture? Munters designs fan wall-based air cooling systems as part of complete, future-ready data center cooling architectures.