What are the reasons of vaccum search in the chiller machine?

all i know vacumnig is to remove water vapor from any DX machine from the house refrigerator to the water cooled chiller ....simple

Avoid formation of water vapor which effect on cooling load for chiller

Vacuum search is used in the kind of chiller machine which is Vapor Absorption Chiller. In evaporator the pressure need to lower down a lot which can be considered as 'vacuum search' - to reduce the refrigerant (water) temperature for making it evaporated. The required heat is collected from the heat exchanger that pass through the evaporator which is hotter than the evaporator chamber.

Der Eng. Sharif

I'm very sorry for late answer, cause I hadn't a good knowledge about baty rules an organize web site. Vacuum search is happened in a lot of kind chiller machines. one of the major reason  the scales in the condenser of chiller, and the  condenser will be under high vapor pressure in the evaporator the pressure vary lower and the refrigerant be reasonable heat exchange with evaporate-water so the evaporator became under vacuum or (low pressure ). So the high pressure vapor in the condenser that pass through evaporate the like storm sound .