A refrigeration cycle apparatus includes; an air heat exchanger; a first expansion valve; a water heat exchanger; a flow passage switching device provided to a discharge part of a compressor; an injection pipe branched from a branch portion of a refrigerant pipe connecting the water heat exchanger with the first expansion valve, and is connected to an injection port of the compressor; a second expansion valve provided to the injection pipe; and an internal heat exchanger configured to exchange heat between refrigerant flowing between the water heat exchanger and the branch portion and refrigerant flowing from the second expansion valve and the injection pipe. The branch portion is provided downstream of the internal heat exchanger and upstream of the first expansion valve in a flow direction of the refrigerant when the flow passage switching device is operated in the first state.

A refrigeration cycle apparatus includes; an air heat exchanger; a first expansion valve; a water heat exchanger; a flow passage switching device provided to a discharge part of a compressor; an injection pipe branched from a branch portion of a refrigerant pipe connecting the water heat exchanger with the first expansion valve, and is connected to an injection port of the compressor; a second expansion valve provided to the injection pipe; and an internal heat exchanger configured to exchange heat between refrigerant flowing between the water heat exchanger and the branch portion and refrigerant flowing from the second expansion valve and the injection pipe. The branch portion is provided downstream of the internal heat exchanger and upstream of the first expansion valve in a flow direction of the refrigerant when the flow passage switching device is operated in the first state.

An air-conditioning apparatus includes a compressor, a four-way valve, expansion means, and an indoor heat exchanger, and further includes a check valve disposed between a discharge side of the compressor and the four-way valve, a first solenoid valve disposed between the expansion means and the indoor heat exchanger, and a controller. Opening and closing of the first solenoid valve are controllable. The controller switches the four-way valve and switches the first solenoid valve between open and closed states. When a heating operation is stopped, the controller switches the four-way valve from connection for the heating operation to connection for a cooling operation, closes the first solenoid valve, and then stops the compressor.

A six-way directional valve (100), an outdoor unit (1000) having the same and an air conditioner are provided. The six-way directional valve (100) includes: a valve body (1), defining a valve cavity (5) therein, the valve cavity (5) having a first side wall (11) and a second side wall (12) disposed oppositely to each other, the valve body (1) being provided with a first connecting pipe (A) to a sixth connecting pipe (F); a valve spool (2), movably disposed in the valve cavity (5), a first chamber (21) being defined between the valve spool (2) and the first side wall (11), a second chamber (22) being defined between the valve spool (2) and the second side wall (12), and a third chamber (23) being defined between the valve spool (2), the first side wall (11) and the second side wall (12); and a pilot valve assembly (4).

A header tube assembly is disclosed and can include an outer tube, an inner tube, and a flow valve. Each of the outer and inner tubes can include an open end and a closed end, as well as a plurality of apertures extending through a sidewall of the outer tube and inner tube, respectively. The apertures of the inner tube can permit a flow of refrigerant between an internal volume of the inner tube and a gap between the inner and outer tubes, and the apertures of the outer tube can permit a flow of refrigerant between the internal volume of the outer tube and a plurality of refrigerant circuits in a heat exchanger. The flow valve can be configured to selectively prevent refrigerant from flowing between the gap and the open end of the outer tube, depending on a direction of refrigerant flow through the header tube assembly.

A header tube assembly is disclosed and can include an outer tube, an inner tube, and a flow valve. Each of the outer and inner tubes can include an open end and a closed end, as well as a plurality of apertures extending through a sidewall of the outer tube and inner tube, respectively. The apertures of the inner tube can permit a flow of refrigerant between an internal volume of the inner tube and a gap between the inner and outer tubes, and the apertures of the outer tube can permit a flow of refrigerant between the internal volume of the outer tube and a plurality of refrigerant circuits in a heat exchanger. The flow valve can be configured to selectively prevent refrigerant from flowing between the gap and the open end of the outer tube, depending on a direction of refrigerant flow through the header tube assembly.

A refrigerant loop of a vapor injection heat pump includes a compressor, first and second expansion valves, and first and second separator valves. The separator valves allow an entire refrigerant flow to pass therethrough or operate to separate vapor and liquid components of expanded refrigerant and inject the vapor component into a suction port of the compressor. Vapor injection occurs in both heating and cooling modes of operation and may depend upon an ambient condition (e.g., high or low ambient temperatures). An accumulator receives an output refrigerant of the heat exchangers dependent upon the mode and directs a vapor component into another suction port of the compressor. A control module controls at least the first and second expansion valves and first and second separator valves dependent upon the mode of operation which include, among others, heating, cooling, and dehumidification and re-heating.

A refrigerant loop of a vapor injection heat pump includes a compressor, first and second expansion valves, and first and second separator valves. The separator valves allow an entire refrigerant flow to pass therethrough or operate to separate vapor and liquid components of expanded refrigerant and inject the vapor component into a suction port of the compressor. Vapor injection occurs in both heating and cooling modes of operation and may depend upon an ambient condition (e.g., high or low ambient temperatures). An accumulator receives an output refrigerant of the heat exchangers dependent upon the mode and directs a vapor component into another suction port of the compressor. A control module controls at least the first and second expansion valves and first and second separator valves dependent upon the mode of operation which include, among others, heating, cooling, and dehumidification and re-heating.

An HVAC system, including a reversing valve including a first port, a second port, and a third port, wherein the reversing valve may be placed into a first position in which the first port is operably coupled to the second port for the flow of refrigerant therebetween, and a second position in which the second port is operably coupled to the third port for the flow of refrigerant therebetween, a first HVAC component operably coupled to the first port, a second HVAC component operably coupled to the second port, and a third HVAC component operably coupled to the third port.

A heat-pump system may include an outdoor heat exchanger, an expansion device, an indoor heat exchanger, a compressor, and a multiway valve. The expansion device is in fluid communication with the outdoor heat exchanger. The indoor heat exchanger is in fluid communication with the expansion device. The compressor circulates working fluid through the indoor and outdoor heat exchangers. The multiway valve may be movable between a first position corresponding to a cooling mode of the heat-pump system and a second position corresponding to a heating mode of the heat-pump system. The working fluid flows in the same direction through the outdoor heat exchanger in the cooling mode and in the heating mode, and the working fluid flows in the same direction through the indoor heat exchanger in the cooling mode and in the heating mode.