GERMANY: Italian company HiRef SpA is applying Bitzer screw compressors to amazing a computing centre adiabatically with air-to-air warmth exchangers.
HiRef SpA, a specialist in air conditioning devices for information centre and telecoms, had the process of designing a cooling program in cooperation with Cooltec Techniques Kälte Klima GmbH for a computing centre in the German town of Offenbach.
A very long-term customer of Bitzer, HiRef observed a sustainable refrigerant being of essential great importance, along with high effectiveness at complete and section load. HiRef opted for an unconventional solution – for the first time, 96 screw compressors with external frequency inverters were set up in the 48 cooling units in its place of scroll compressors. These use R513A but can be transformed to use the minimal GWP HFO refrigerant R1234ze at a afterwards day.
As one of the initial HiRef units with the adiabatic program, this challenge was of specific significance. “We needed there to be no doubt that the top quality of our environmentally friendly and sustainable remedy surpasses everybody else in the market – that is a different cause why we applied screw compressors as a substitute of scrolls,” discussed HiRef business director Wolfgang Fels.
With screw compressors, selected temperature concentrations can be preserved exactly and regularly. If the preset most temperature established issue is exceeded, the evaporative cooling system lowers the condensing temperature and thus the electricity consumption. Pace-controlled by frequency inverters, the screw compressors provide whole mechanical backup for the cooling capacity.
“Capacity control will make the screw compressors really strength successful at entire and aspect load,” Fels extra.
Every program has a cooling capacity of 200kW and is fitted with EC followers and a distinctive significant-effectiveness crossflow heat exchanger with a corrosion resistant epoxy coating. The double-ended parallel electrical feed has a rapid-commence attribute as perfectly as uninterrupted handle of the power provide.
The cooling approach is centered on three distinctive concepts: full cost-free cooling with a wintertime bypass, demands-based mostly, modulating, mechanical cooling with maximised totally free cooling, and modulated, mechanical cooling with an adiabatic spray technique in the condenser.
The integrated oil separator in the Bitzer CSH65 screw compressors and the designed-in suction-fuel-cooled motor simplify method integration and, in accordance to Bitzer, make it possible for for a compact, charge-economical method layout.
Moreover reduce lifetime cycle charges and 24/7 reliability below any operating circumstances, seem insulation was of critical significance in this challenge. The compressors’ distinctive enclosure assures optimum sound insulation, although the built-in pulsation mufflers decrease sound on the exhaust air aspect.