The all-important energy efficiency parameter for cooling is the Energy Efficiency Ratio (EER), This defines the ratio of cooling output to the electrical power used. The higher the EER, the better. Conventional chillers that use hot-gas bypass control exhibit an EER of 1. The new Blue e+ chillers from Rittal achieve an EER of up to 4. At the heart of this efficiency enhancement is a variable-speed compressor that always provides just as much cooling output as is currently required. Rittal uses precisely controlled DC synchronous motors to drive the compressors. This ensures the Blue e+ chillers run at optimum speed, saving up to 70 per cent of energy compared to chillers using hot-gas bypass control. Another technical innovation is the micro-channel technology in the heat exchangers, which helps reduce the volume of refrigerant used by up to 55 per cent and thus benefits the environment.
The Blue e+ chiller series comprises three models with cooling outputs of 2.5, 4 or 5.5 kilowatts. An integrated flow sensor in the cooling medium circuit and fill level monitoring further boost reliability. There is also an overflow valve installed in the cooling medium circuit that opens automatically as soon as the cooling medium circuit is closed at the point of use. A filter mat monitoring system promptly notifies the user when the filter mat needs to be replaced. The units can be used worldwide with all common mains frequencies and voltages – and are very user friendly. The control panel, which features a touchscreen display, depicts all messages in plain text – and in 21 languages. The Blue e+ app transmits data wirelessly, while RiDiag III parameterisation and diagnosis software can also be used with the new series via a USB connection or by linking up to the IoT interface through a range of network protocols.