Thermal Wall FAQ
Everything you need to know about MEWALL: Mitsubishi Electric’s thermal wall cooling solution designed for high density IT loads.
Thermal wall cooling systems differ from traditional CRAC and CRAH units by integrating directly into the data hall structure and using chilled water to deliver high-capacity, efficient cooling (500 kW+ per unit).
Unlike CRAC and CRAH units, which rely on raised floors and centralized air distribution, thermal walls pull hot air from a rear corridor and supply cool air uniformly, improving airflow and space efficiency.
While installation can be more complex and requires dedicated infrastructure, thermal walls offer superior scalability and energy efficiency for large, high-density data centers.
🔗 Read more about the differences in “Understanding Data Center Cooling Technology.”
Thermal walls do not require cold aisle containment or a raised floor, but are optimized with a hot aisle to avoid air mixing.
🔗 Discover how aisle containment is directly linked to cooling efficiency. Learn more!
- High-Density Cooling
MEWALL is engineered for hyperscale and colocation environments, supporting taller racks and high intake temperatures without sacrificing performance. - Energy Efficiency
Advanced airflow control strategies—like constant airflow or differential pressure—optimize fan speed and reduce energy consumption. - Space Optimization
Installed along perimeter walls, MEWALL eliminates the need for raised floors and allows for tighter rack spacing and vertical stacking. Zero side clearance between units maximizes cooling capacity per linear foot. - Simplified Installation & Maintenance
Front-access design and pre-installed piping streamline both setup and servicing. No cold aisle containment is required, simplifying airflow management. - Reliable & Scalable
MEWALL integrates with chilled water systems, supports multiple models (e.g., 402 & 462), and ensures continuous cooling with minimal downtime.
🔗 Learn more about MEWALL
While PUE is a facility-wide metric, a high-efficiency thermal wall system can play a key role in improving it by reducing the power consumed for cooling, especially when paired with advanced controls and variable-speed fans.
Operating at higher intake air temperatures—within ASHRAE-recommended limits—further enhances this benefit.
Warmer intake air reduces the workload on cooling systems, allowing components like chillers and air handlers to run more efficiently and consume less energy.
The MEWALL is specifically optimized for these higher intake temperatures. It delivers precise airflow control and variable-speed operation to maintain consistent thermal performance.
This optimization supports higher chilled water setpoints and enables greater use of economizers, both of which contribute to lower overall cooling energy consumption.
By combining intelligent control with a design built for elevated intake conditions, our thermal wall system helps reduce non-IT power use and directly supports a lower PUE for the facility.
MEWALL is configurable to the unique requirements of your data center and is capable of a Net Sensible Cooling Capacity of up to 552KW.
🔗 Check out MEWALL’s specifications
MEWALL supports scalability through a flexible design approach. With two model options (402 & 462) sharing the same footprint, it simplifies planning and allows for future capacity growth without major redesign.
This consistency enables phased deployment—so cooling capacity can be added as IT load increases, helping to avoid overbuilding and supporting faster, more efficient expansion.
Not requiring a raised floor simplifies installation, improves airflow consistency, and supports modern data center demands more effectively.
- By eliminating the need for a raised floor, this cooling approach avoids common challenges like maintaining a clean, unobstructed underfloor space and managing cables effectively.
- There’s no risk of uneven airflow caused by underfloor pressurization issues or temperature gradients as cool air rises through tall racks.
- It removes concerns about the raised floor’s load-bearing limits, which can be insufficient for today’s heavy, high-density equipment racks.
Remote functions generally refer to the ability to monitor, control, or manage equipment from a distance—without being physically at the unit itself. In the context of cooling systems like MEWALL, remote functions could include:
- Remote Monitoring: Viewing system status, alarms, and performance data from a remote location via BMS (Building Management System) or DCIM (Data Center Infrastructure Management).
- Remote Control: Sending commands to adjust operating parameters (like temperature setpoints or fan speeds) from a centralized control system.
- Remote Display: The remote display allows you to monitor and control multiple connected units from a single interface. It’s a required component for group control, giving centralized access to all units in the group while operating within the system’s own internal control network.
The MEWALL can easily perform a variety of group control functions that translate into increased efficiency, reliability, and cost savings.
Group Control Functions include:
- Automatic Master Unit Assignment
- Standby Unit Rotation & Activation
- Enhanced Airflow Standby Mode
- Average Temperature Control
- Active Load Distribution
- Localized Hot & Cold Spot Adjustment
- Active Pressure Load
- Fan Load Distribution Control
MEWALL units communicate directly with each other over a shielded twisted-pair bus, enabling decentralized group control without relying on a central controller.
This peer-to-peer communication allows the units to function as a unified system, sharing data continuously and dynamically adjusting their performance based on real-time conditions.
By working collaboratively through group control, the system delivers precise and efficient cooling tailored to current demand.
This decentralized approach enhances overall system resilience, allowing it to better handle fluctuations in load and respond effectively to potential failures.
The MEWALL is available in two models, the 402 and the 462.
| Model | H (in) | L (in) | D (in) |
| 402 | 138 | 142 | 63 |
| 462 | 157 | 142 | 63 |
🔗 Check out the full Specification Table or download the full Specification here.
Connection to power and water necessitates downtime for each system during initial setup, but data center functions are largely uninhibited since connection points are quickly established upon placement of the unit with proper planning.
Our team can assist with the planning of your installation.
🔗 Contact us to learn more!
The placement of each unit is dependent on your floor layout, air containment, rack design, and specific IT equipment being used in the space.
Generally, MEWALL produces a low airspeed, allowing for closer proximity to IT equipment (we recommend a minimum of 5 ft (1.5 m)).
🔗 Contact us with your spacing requirement questions.
Each application is unique. Reach out to our Project Application Engineering team for more information.
The system can be set up and configured to respond to load spikes through intelligent controls.
While it’s not fully autonomous, once properly configured, individual fans, modules, or entire units can ramp up cooling in response to hot spots generated by IT equipment in specific areas of the white space.
This means precise cooling is applied to the hot spot without increasing the output of the entire system.
Thermal wall systems, like MEWALL, can support any Tier level, but it’s not the product itself that determines compliance—it’s how it’s integrated into the overall system design.
For lower-tier facilities (Tier I or II), a single unit may be sufficient. However, for higher-tier environments (Tier III or IV), the design must include redundancy—such as N+1 or 2N configurations using standby fans or additional modules—to ensure continued operation in the event of a failure.
In summary, the ability of MEWALL to support a specific Tier depends on how it’s applied within the cooling strategy—not on the unit alone.
Our IT Cooling service team is available to setup preventative maintenance visits for your systems.
🔗 Contact us to get started!
In general, Mitsubishi Electric recommends quarterly preventative maintenance for the MEWALL.
Some key features that minimize downtime and reduce costs during service include:
- Access to the rear of the unit has been designed into the unit.
- Filters are easy to remove and a pivoting fan door allows technicians to access the coils, controls, valves, and fans for repair or replacement.
- Faulty fans can be isolated via optional blank-off plates so the unit can continue running. These plates are designed to block airflow through the non-operational fan, helping maintain overall system performance. They are available as a kit for customer installation.
🔗 Contact us to learn more.
Maintenance for thermal wall systems differs from traditional cooling units. While they eliminate large standalone cooling equipment, routine tasks like filter replacement, coil cleaning, and fan maintenance are still required.
Since thermal walls don’t contain compressors or refrigerant piping like conventional systems, maintenance on the unit itself is less complex.
However, because these systems rely on chilled water for cooling, proper maintenance of the supporting infrastructure—pumps, valves, and piping—becomes critical.
Ongoing maintenance costs are generally lower due to fewer mechanical components requiring service. Typical tasks include:
- Routine filter replacement
- Periodic coil cleaning
- Occasional fan servicing or repair
🔗 Contact us to learn more!
The lifespan of a thermal wall system depends on several factors, including fan type, operating conditions, maintenance practices, and duty hours.
As a general guideline: EC (Electronically Commutated) fans typically operate for 60,000 to 100,000 hours, which translates to about 7–11 years under continuous, 24/7 use.
Thermal wall systems can last 15–20 years with proper maintenance and occasional component replacements, such as individual fans and valves.