Abstract: In an air-conditioning apparatus, an outdoor unit installed in an outdoor space and an indoor unit installed in an indoor space are connected by refrigerant pipes to form a refrigerant circuit. One or more pairs of valve kits are provided at the refrigerant pipes by which the outdoor unit and the indoor unit are connected, and allow a pair of additional refrigerant pipes on an inflow side and an outflow side to be connected to one of the one or more pairs of valve kits, the pair of additional refrigerant pipes being additionally provided to enable a new indoor unit to be added after installation of the air-conditioning apparatus. The valve kits of the one or more pairs of valve kits have respective distal end portions that are inclined upwards relative to a horizontal direction. The distal end portions each allow an associated one of the additional refrigerant pipe to be connected to the distal end portion.

Abstract: The air-conditioning apparatus includes: a refrigerant circuit in which a compressor, an outdoor heat exchanger, the expansion valve, and an indoor heat exchanger are connected by pipes; and a controller. The controller includes a valve opening-degree adjusting module, a flow-rate determination module, and a clogging determination module.

Abstract: In an air-conditioning apparatus, an outdoor unit installed in an outdoor space and an indoor unit installed in an indoor space are connected by refrigerant pipes to form a refrigerant circuit. One or more pairs of valve kits are provided at the refrigerant pipes by which the outdoor unit and the indoor unit are connected, and allow a pair of additional refrigerant pipes on an inflow side and an outflow side to be connected to one of the one or more pairs of valve kits, the pair of additional refrigerant pipes being additionally provided to enable a new indoor unit to be added after installation of the air-conditioning apparatus. The valve kits of the one or more pairs of valve kits have respective distal end portions that are inclined upwards relative to a horizontal direction. The distal end portions each allow an associated one of the additional refrigerant pipe to be connected to the distal end portion.

Abstract: An air-conditioning apparatus is configured to melt a large amount of adhering frost while maintaining an appropriate operation of a compressor by setting a defrosting operation time period depending on a low pressure of the compressor. The air-conditioning apparatus includes a refrigerant circuit including the compressor, a refrigerant flow switching device, a heat source-side heat exchanger, an expansion device, and a use-side heat exchanger, which are connected via a refrigerant pipe to form a refrigeration cycle, a pressure sensor configured to detect a pressure on a suction side of the compressor, and a controller configured to control, in a defrosting operation, the refrigerant flow switching device to supply compressed refrigerant from the compressor to the heat source-side heat exchanger, compare a value detected by the pressure sensor with a first threshold value, and change the defrosting operation time period based on a result of the comparison.

Abstract: An air-conditioning device which melts a large amount of frost deposited thereon while maintaining the proper operation of a compressor by setting the defrosting operation time according to the low pressure of the compressor. This air-conditioning device has: a refrigerant circuit which has a compressor, a refrigerant flow path switching device, a heat-source-side heat exchanger, a throttle device, and a use-side heat exchanger being connected by refrigerant pipes, and configures a refrigeration cycle; a pressure sensor which detects the pressure on the intake side of the compressor; and a control device which, during defrosting operation, controls the refrigerant flow path switching device and supplies the compressed refrigerant from the compressor to the heat-source-side heat exchanger, compares the detection value of the compressor sensor and a first threshold value, and changes defrosting operation time on the basis of the comparison result.