Daikin Industries, Ltd.

Yukako Kanazawa

Junichi Shimoda

Tatsuya Makino

Yuko Ishida

Yoshiaki Yumoto

Shouhei Miyatani

Keitarou Hoshika

Toshihiko Takayama

In an air conditioner, a control section controls at least the indoor expansion valve. The indoor expansion valve has a degree of opening that is controllable. The control section has a condensate formation suppressing control mode and a normal heating control mode. The condensate formation suppressing control mode is performed in a case where a predetermined condensate formation condition is satisfied. The predetermined condensate formation condition relates to generation of condensate formation on the connecting section. The normal heating control mode is performed in cases other than the case where the predetermined condensate formation condition is satisfied. The control section increases the opening degree of the indoor expansion valve when the condensate formation suppressing control mode is performed compared to a case when the normal heating control mode is performed.

Air conditioner

An indoor unit of an air conditioner indicates cooling or heating operation states not obtained from an outdoor unit of the air conditioner. The indoor unit includes an indoor control section having first and second control modes. The second control mode is performed in a case when information ascertained by a second information ascertaining section satisfies a predetermined condition. In the first control mode, the opening degree of the indoor expansion valve is controlled so that the degree of superheat satisfies a predetermined superheat condition. In the second control mode, the opening degree of the indoor expansion valve is controlled such that the opening degree is larger than in the first control mode, or the opening degree of the indoor expansion valve is controlled using a modified first control mode by setting a lower limit opening degree narrowing an adjustable range of the opening degree in the first control mode.

Indoor unit of air conditioner

An air conditioning apparatus includes a refrigerant circuit having a compressor, a radiator, an upstream side expansion valve, a receiver, a downstream side expansion valve, an evaporator, and a receiver gas vent pipe. Gas vent control is performed so that gas refrigerant is led from a receiver to the suction side of a compressor via a receiver gas vent pipe by opening a receiver gas vent valve. Upstream side expansion valve subcooling control is performed so that the opening of an upstream side expansion valve is changed such that the subcooling of refrigerant is set to target subcooling at the outlet of a radiator. Downstream side expansion valve suction wetting control is performed so that the opening of a downstream side expansion valve is changed such that refrigerant is in a wetting state and the dryness is set to target dryness at the outlet of an evaporator.

Air conditioning apparatus

An air conditioning apparatus has a refrigerant circuit in which a compressor, a four-way switching valve, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger are interconnected. The outdoor heat exchanger uses multi-hole flat tubes as heat transfer tubes. When stopping a heating operation, the air conditioning apparatus performs pressure equalization control that switches the four-way switching valve from a heating cycle state to a cooling cycle state, thereafter stops the compressor, and equalizes the pressure in the refrigerant circuit.

An air-conditioning apparatus includes an outdoor unit, an indoor unit having an indoor heat exchanger, and a controller for executing a pump down operation. The outdoor unit has an accumulator of a capacity (Va), a compressor, an outdoor heat exchanger, an expansion valve, a large-diameter tube, which are joined by refrigerant pipes. The capacity (Vhi) of the indoor heat exchanger is greater than the capacity (Vho) of the outdoor heat exchanger. The large-diameter tube, which is larger in diameter than the refrigerant pipes, is provided so that the capacity (Vt) of the large-diameter tube satisfies the formula: capacity (Vt)&#x3e;capacity (Vhi)&#x2212;capacity (Vho)&#x2212;capacity (Va).

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Sakai, Japan

Yukako Kanazawa