Vapor compression system and method

The steam compressing device (10), comprising an evaporator (16), a compressor (12) and a condenser (14); they each other to form a closed ring connected system. An embodiments, the multifunctional valve (18) is connected with the heat transfer liquid and compressor (12) and steam from the condenser (14) liquefication. A saturated steam pipeline is connected with the multifunctional valve (18) and evaporator (16), a determines the size of the saturated steam pipeline, in order to the heat transfer liquid inlet the evaporator (16) of said via the multifunctional valve (18) and heat transfer liquid formed to be the saturated steam. Back pumping pipeline a (30) return compressor (12) and heat transfer liquid through the controlling temperature, the multifunctional valve (18) can measure through the heat transfer liquid flow pump, the pipeline of the evaporator (16) and a compressor (12) is connected. Multifunctional valve (18) are independent control passages of the refrigerating systematically to defrost operation, when defrosts of the water and air supersaturated steam pipeline of the door sleeve (28) and evaporator (16), then the reducing the side of the system defrosted to require, improved integrated system and.