Roller’s new state-of-the-art test cell
27th May 2026
GERMANY: Equipment manufacturer Walter Roller has invested in a new test cell that enables a wide range of tests under precisely controlled conditions.
The design of the cell is based on a dual-chamber principle. An inner test cell is completely enclosed by an outer casing. By bringing both chambers to the same temperature, all transmission-related interferences can be eliminated.
The inner chamber can be cooled using an air cooler via direct CO2 evaporation or indirectly via a heat transfer fluid such as water or brine, while simultaneously being heated by electric heating elements.
Once a stable equilibrium is reached, the heat input and output can be precisely determined by balancing the heat. Additionally, the refrigerant mass flow rate in the liquid line of the test specimen is measured using a Coriolis flow meter. The combination of these two methods ensures that the line performance can be determined and reported as accurately as possible and in accordance with standards.
Cooling is provided by a subcritical CO2 compound system, specifically designed to Walter Roller’s requirements. This ensures compliance with the DIN EN 328, the standard for performance measurement of fan air coolers. The test range covers cooling capacities from 3kW to 15kW and temperatures between -31°C and 0°C. Additionally, water and brine air coolers from the H₂OCooler series can also be tested.
To simulate realistic to extreme climatic scenarios in the test cell, a high-performance steam generation system was integrated. This allows for the simulation of different icing conditions on deep-freeze evaporators. This, in turn, enables the optimisation of defrosting systems under real-world load conditions.
Walter Roller recognises that this area is gaining further importance because strict safety requirements apply to the use of flammable refrigerants. All surface temperatures must be at least 100K below the respective ignition temperature of the refrigerant or its components.
As a result, the defrosting systems of Walter Roller’s new MultiRef series, which operate with multiple refrigerants, are being redesigned to ensure compliance. This relieves customers of the worry about the complex temperature limits or the conformity of the individual components of the air cooler.
The new test chamber allows the development team at Walter Roller to precisely coordinate defrosting systems, fan units, valve installations, and other components. The company says that this results in reduced commissioning time and provides practical plug-and-play solutions that significantly shorten on-site installation times.
