INTEGRATED REFRIGERATING/FREEZING SYSTEM AND DEFROST METHOD

摘要

A medium and low-temperature integrated refrigeration/freezing system (100) has the function of discharge gas defrosting. It comprises medium and low-temperature compressors sets (120, 122) and medium and low-temperature evaporators, as well as control valves (141, 142, 143, 144), adjusting valves (145, 146), one-way valves (147, 148) and expansion valves (150, 152, 154), and the switching between a refrigerating cycle and the discharge gas defrosting cycle is performed by the combination of actions between multiple control valves. When a first control valve is opened, a second valve is closed and a fourth valve is closed to the refrigerant pipeline to said reservoir, the refrigerating cycle operation is performed; and when the first control valve is closed, the second valve is opened and the fourth valve is closed to the refrigerant pipeline of an intercooler (128), the discharge gas defrosting operation is performed.