To be observed for tandem and 2-stage compressors

Oil equalisation for semi-hermetic tandem compressors

When tandem compressors are operated with frequency inverter, the oil level between both compressor sides may differ. Thus, an oil level control system or oil and gas equalisation must be installed between the two sides.

RI valve for semi-hermetic 2-stage compressors

For 2-stage compressors, sufficient superheat at the refrigerant injection (RI) valve must be ensured over the entire speed range. Therefore select a valve suitable for the application.