Patent ID: 8713958
Filing Date: 2014-05-06
Classification: F25B

Abstract:
1. An air conditioner comprising: a first outdoor unit provided with a first compressor, a first outdoor heat exchanger, and a first outdoor expansion valve; and a plurality of indoor units connected to the first outdoor unit by an inter-unit pipeline and provided with indoor heat exchangers, one end of the first outdoor heat exchanger selectively branched and connected to a refrigerant discharge pipe and a refrigerant sucking pipe of the first compressor, the inter-unit pipeline including a high-pressure gas pipe connected to the refrigerant discharge pipe, a low-pressure gas pipe connected to the refrigerant sucking pipe, and a fluid pipe connected to the other end of the first outdoor heat exchanger, one end of the indoor heat exchanger being selectively branched and connected to the high-pressure gas pipe and the low-pressure gas pipe, and the other end of the indoor heat exchanger being connected to the fluid pipe through a fluid branch pipe so that the plurality of the indoor units can perform a cooling operation or a heating operation at the same time or the cooling operation and the heating operation can be performed in a mixed manner, wherein a second outdoor unit provided with a second compressor, a second outdoor heat exchanger, and a second outdoor expansion valve and connected by two pipelines of a gas pipe and a fluid pipe and a valve-element kit having a channel switching valve that connects the fluid pipe of the second outdoor unit to the fluid pipe of the inter-unit pipeline and selectively connects the gas pipe of the second outdoor unit to the high-pressure gas pipe or the low-pressure gas pipe of the inter-unit pipeline are provided, the first outdoor unit is provided with a first outdoor unit valve element that makes the refrigerant discharge pipe and the high-pressure gas pipe capable of communicating with each other, each of the plurality of indoor units comprises a high-pressure gas branch pipe connected to the high-pressure gas pipe through a first indoor unit valve and a low-pressure gas branch pipe connected to the low-pressure gas pipe through a second indoor unit valve, and in a case of the cooling operation of the plurality of indoor units at the same time, a controller is configured to control the first outdoor unit valve element to shut off communication between the refrigerant discharge pipe of the first compressor and the high-pressure gas pipe, control the plurality of indoor units to close the first indoor unit valve and open the second indoor unit valve in a part of the plurality of indoor units while to open the first indoor unit valve and close the second indoor unit valve in the remaining plurality of indoor units, and switch the channel switching valve to connect the gas pipe of the second outdoor unit to the high-pressure gas pipe.