| 摘要 |
PURPOSE:To allow indoor units of an air conditioner, which is capable of performing simultaneous cooling and heating operation, to individually, selectively perform either cooling or heating operation at the same time by a method wherein at defrosting operation, a four-way valve is changed over, a first manifold and first flow control valves are closed, and second and fourth control valves are opened. CONSTITUTION:At defrosting operation, high temperature, high pressure refrigerant gas discharged from a compressor 1 releases heat at a heat source side exchanger 3 to become cool and condenses while it melts the frost deposited on the heat source side heat exchanger 3. After that, the liquid refrigerant flows into a first connecting pipe 6 through a third check valve 32, a second connecting pipe 7, a gas-liquid separator 12, a second flow control valve 13 and a fourth flow control valve 17, and is sucked by the compressor 1 via a fourth check valve 33, a four-way valve 2 at a heat source apparatus A and an accumulator 4. At this time, first and second on-off valves 8a and 8b of changeover valves 8 of the first manifold 10 are closed. Further, all the first control valves 9 of the indoor units B, C and D are closed. |
