| 摘要 |
PURPOSE:To make it possible to satisfy the demand for both cooling and heating at the same time in a large building by controlling a refrigerant flow passage with a multi-control unit, and enabling simultaneous cooling and heating operation in compliance with discreet demand per indoor unit. CONSTITUTION:When indoor units 11 and 12 are demanded to perform heating operation while an indoor unit 13 is called for to carry out cooling operation, for example, a multi-control unit B selects heating operation mode since the heating load is greater than the cooling load. As a result, two way valves 29a, 29b, and 29c, 30a, and 30b are closed while two way valves 23 of an outdoor unit A is closed and the valve 26 is opened. A high temperature discharged refrigerant from a compressor 1 is introduced into the indoor units 11 and 12 so that it may return by way of flow rate control valves 14a and 14b, a heating expansion valve 4, and an outdoor heat exchanger 3. At the same time, a high pressure refrigerant cooled by the indoor units 11 and 12 is introduced into the indoor unit 13 by way of a flow rate control valve 14c and a cooling expansion valve 15 and returns to the compressor 1 after cooling is over. It is, therefore, possible to perform both cooling and heating operation simultane ously. |
