Is the direction of rotation of compressors important?
With 1phase compressors the rotation is determined by the way the compressor is wired and should not be altered. On 3 phase compressors it depends on the type of oil pump or the method of the compression. E.g the centrifugal style of oil feed designed into Maneurop reciprocating compressors can rotate in either direction but it is important with Scroll compressors that the direction of rotation is correct, because the scroll will only pump in one direction. To check the rotation a set of gauges should be connected to the high and low side of the compressor. On start up, if the compressor is noisy and the pressures do not fall on the low side and rise on the high side the direction of rotation is incorrect and two of the electrical phases have to be changed around. It is advisable to fit a phase correction module that would cut off the compressor in the event of a phase change.
