The inventive central air-conditioning machine set comprises a refrigerating plant and an energy-storage heat-exchanging unit, the water inlet of which is connected with the water inlet of an indoor plate heat exchanger and the water outlet of which is connected with the water outlet of the indoor plate heat exchanger. The refrigerant steam outlet of the energy-storage heat-exchanging unit is connected with a four-way valve, an inlet of a low-pressure gas-liquid separator and the refrigerant steam outlet of the indoor plate heat exchanger separately. The refrigerant liquid inlet of the energy-storage heat-exchanging unit is connected with a throttle mechanism and the refrigerant liquid inlet of the indoor plate heat exchanger separately. |