Once satisfactory performance has been achieved and recorded, the compressor is disconnected from the test chiller, sealed off, evacuated, and charged with dry nitrogen.  It is then dipped into a tank of water, for the second time, to check for gasket leaks that can be a nuisance in the field.  If a leak is present the pressure of the nitrogen will cause bubbles to form under water.  They can then be corrected and this procedure repeated.  Leak check is done on every compressor before and after it is run under-load on our variable tonnage test chiller.