| 主权项 |
1. A system for defrosting refrigeration units, the system comprising:
single or multiple refrigeration units, each of said refrigeration units comprising a compressor, a condenser, an evaporator, and an expansion valve, wherein each of said refrigeration units is operable in:
a refrigeration mode during which said refrigeration units are applied for providing useful cooling, anda defrost mode during which a gas defrost method is applied for removing frost from said evaporator; a condenser fluid circuit comprising at least a condenser fluid supply line and a condenser fluid return line, each coupled to the condenser and configured to circulate a condenser fluid to the condenser during the refrigeration mode; a defrost heat exchanger disposed between the evaporator and the compressor; a defrost fluid circuit comprising at least a defrost fluid supply line and a defrost fluid return line, each coupled to the condenser and configured to circulate a defrost fluid to the condenser during the defrost mode, and each coupled to the defrost heat exchanger and configured to circulate the defrost fluid to the defrost heat exchanger during the defrost mode; a condenser inlet valve having a first inlet port fluidly connected to the condenser fluid supply line and a second inlet port fluidly connected to defrost fluid supply line, and an outlet port fluidly connected to an inlet of the condenser; and a condenser outlet valve having a first outlet port fluidly connected to the condenser fluid return line and a second outlet port fluidly connected to defrost fluid return line, and an inlet port fluidly connected to an outlet of the condenser. |
