York centrifugal chillers have compressors with magnetic bearings
The York YMC2 range of chillers from Johnson Controls use centrifugal compressors with magnetic bearings. The compressor is of the company’s own manufacture [not Turbocor in other words] and uses R134a. This magnetic-bearing technology has been used by Johnson Controls in naval applications for the past decade. These chillers are said to be 10% more efficient than conventional variable-speed chillers. Cooling capacities are from 750 to 1330 kW.
Other features of these chillers include improvements to the OptiSpeed drive. Evaporator efficiency has been improved with a ‘falling-film’ design, and advantage is taken of cooling-tower water at low temperature to save energy.
Noise at full load is 73 dB(A), which is claimed to be about 3 dB(A) less than other chillers with compressors having magnetic bearings.