In the cooling-duty range between 300 and 1,330 kW, air-cooled chillers GEA Heat Exchangers offer increased energy efficiency by an average of 20 percent, says the manufacturer. The company credits the patented, integrated sub-cooler circuits.
Depending on the model, an EER greater than 3.2 is achieved: for 59/50°F (15/10°C) return/supply temperatures, 30 percent ethylene glycol, and 95°F (35°C) air-intake temperature. In comparison to the predecessor range, according to the company, the maximum unit output possible in free-cooling mode is consistently achieved at outdoor temperatures around 35.6°F (2°C). These chillers are suited for facilities that also must be cooled while outdoor temperatures are low such as production facilities and computer centers.
The free-cooling function enables savings because for the GEA GLFC-DA2 range, this function goes into operation when the outside-air temperature falls by 2 K below the return-flow temperature of the medium. Under these conditions, the integrated free-cooling heat exchanger cools the water to the greatest possible extent, and power consumption of the compressors falls appreciably. With low outdoor temperatures, it is even possible to dispense with operation of the compressor entirely. Reduced operating hours of the compressor lower energy consumption and CO2 emission – and extend maintenance intervals.