Air conditioner with dehumidifying and heating operation

An air conditioner, comprising:

• a compressor for sucking and compressing refrigerant;
• first and second heat exchangers for performing a heat exchange between refrigerant and air to be blown into a compartment;
• a third heat exchanger for performing a heat exchange between refrigerant and outside air;
• a switching device for switching between a first circulation state where refrigerant discharged from the compressor flows through the first heat exchanger, the second heat exchanger and the third heat exchanger in this order, and a second circulation state where the refrigerant discharged from the compressor flows through the first heat exchanger, the third heat exchanger and the second heat exchanger in this order;
• a first decompression device for decompressing refrigerant flowing out of the first heat exchanger in the first circulation state;
• and
• a second decompression device for decompressing refrigerant flowing out of the third heat exchanger in the second circulation state.

An air conditioner comprising:

• a compressor for sucking and compressing refrigerant;
• first and second heat exchangers for performing a heat exchange between refrigerant and air to be blown into a compartment;
• a third heat exchanger for performing a heat exchange between refrigerant and outside air;
• and
• a switching device for setting one of a first circulation state and a second circulation state, wherein:
• in the first circulation state, refrigerant discharged from the compressor flows through the first heat exchanger, the second heat exchanger and the third heat exchanger, in this order;
• and
• in the second circulations state, the refrigerant discharged from the compressor is supplied to the first heat exchanger and the third heat exchanger while the first heat exchanger and the third heat exchanger are connected in series with respect to a refrigerant flow, and the refrigerant after passing through the first heat exchanger and the third heat exchanger is decompressed and is circulated into the second heat exchanger.

An air conditioner comprising:

• a compressor for sucking and compressing refrigerant;
• a first heat exchanger for performing heat exchange between refrigerant discharged from the compressor and air to be blown into a compartment;
• a first decompression device for decompressing refrigerant flowing from the first heat exchanger;
• a second heat exchanger for performing heat exchange between refrigerant from the first decompression device and air to be blown into the compartment;
• a second decompression device for decompressing refrigerant from the second heat exchanger;
• a third heat exchanger for performing a heat exchange between refrigerant from the second decompression device and outside air outside the compartment;
• and
• a control unit for controlling a throttle opening degree of the second decompression device such that a refrigerant temperature in the second heat exchanger becomes higher than a refrigerant temperature in the third heat exchanger.