HiRef: R744 for the Copenhagen Metro


The Italian company HiRef, in collaboration with distributor Unicool, supplied 4 air-cooled water chillers from the CDA series for the server room of the Copenhagen Metro. Consisting of independent refrigeration circuits with modulating compressors, the units reach a total cooling capacity of 500 kW and use a transcritical system with natural refrigerant R744.

HiRef met the final customer’s needs by offering a customised solution. In fact, the four units, which replaced outdated machines, were installed in sites with significant installation constraints.

The plant’s energy efficiency is another important aspect: the innovative gas cooler pressure optimisation system, a HiRef patent, maximises performance at every operating condition. The R&D department of HiRef and subsidiary Tecno Refrigeration, the Group’s competence centre on CO2, worked collaboratively on the project.

A FAT (Factory Acceptance Tests) was conducted with the customer present at HiRef’s plant in Tribano (Padova – Italy) and technical training was provided to the personnel in charge of installation.

FATs (Factory Acceptance Tests) are part of HiRef testing process. These let end customers or their technical consultants personally ascertain that the equipment complies with project specifications.

Temperature, pressure, flow, and vibration transducers are connected to a monitoring computer that provides readings of the product’s operating parameters, for a complete performance assessment. The data gathered are used to calculate different performance indicators and assess efficiency, energy savings and any other parameter for satisfying project requirements. Measurement of noise emissions is a very important aspect at HiRef, which provides an off-site qualified area compliant with the UNI EN ISO 3746 standard. Thanks to our collaboration with the University of Padua, we can draw on the expertise of academics for certification of acoustic tests. HiRef also has a lab for component thermal stress testing to validate continuous operation at extremely low temperatures (as low as -50 °C).

More information HERE