An outdoor unit of an air-conditioning apparatus includes: a housing configured to form an outer shell; and a heat exchanger provided to extend at a rear portion of the housing from a lower portion toward an upper portion of the housing, wherein the heat exchanger includes a heat exchanger side plate provided on a side portion and having a side plate locking hole at an upper portion, and the housing includes a rear panel being a plate-like part that forms a rear surface and including an upper rear-surface locking claw at an upper portion, the upper rear-surface locking claw being inserted into the side plate locking hole, and a top panel being a plate-like part provided on an upper side of the rear panel and forming a top surface of the housing, the top panel covering the side plate locking hole and the upper rear-surface locking claw.

An outdoor unit of an air-conditioning apparatus includes: a housing configured to form an outer shell; and a heat exchanger provided to extend at a rear portion of the housing from a lower portion toward an upper portion of the housing, wherein the heat exchanger includes a heat exchanger side plate provided on a side portion and having a side plate locking hole at an upper portion, and the housing includes a rear panel being a plate-like part that forms a rear surface and including an upper rear-surface locking claw at an upper portion, the upper rear-surface locking claw being inserted into the side plate locking hole, and a top panel being a plate-like part provided on an upper side of the rear panel and forming a top surface of the housing, the top panel covering the side plate locking hole and the upper rear-surface locking claw.

A subcooler is made up of a plate type heat exchanger. The accumulator is located between a compressor and the subcooler in a width direction of an outdoor unit in a planar view. The subcooler overlaps with the accumulator in the width direction in the planar view. As a result, a compact heat pump can be provided when the subcooler is a plate type heat exchanger.

A subcooler is made up of a plate type heat exchanger. The accumulator is located between a compressor and the subcooler in a width direction of an outdoor unit in a planar view. The subcooler overlaps with the accumulator in the width direction in the planar view. As a result, a compact heat pump can be provided when the subcooler is a plate type heat exchanger.

A condenser, an air conditioner outdoor unit, and an air-conditioning system. The condenser includes at least one row of heat exchange tubes and a plurality of fins arranged along the heat exchange tubes, where any fin is provided with at least one column of through holes, which correspond to the number of rows of the heat exchange tubes, for the heat exchange tubes to pass through; the fins are evenly divided, in the width direction, into at least one basic unit corresponding to the number of rows of the heat exchange tubes; the width of any basic unit is greater than 18.2 mm; and the center distance between two adjacent through holes from among any column of through holes is less than 21 mm. As a result, the heat exchange efficiency can be improved, and the energy efficiency can also be improved.

A condenser, an air conditioner outdoor unit, and an air-conditioning system. The condenser includes at least one row of heat exchange tubes and a plurality of fins arranged along the heat exchange tubes, where any fin is provided with at least one column of through holes, which correspond to the number of rows of the heat exchange tubes, for the heat exchange tubes to pass through; the fins are evenly divided, in the width direction, into at least one basic unit corresponding to the number of rows of the heat exchange tubes; the width of any basic unit is greater than 18.2 mm; and the center distance between two adjacent through holes from among any column of through holes is less than 21 mm. As a result, the heat exchange efficiency can be improved, and the energy efficiency can also be improved.

An air-conditioning apparatus includes: a housing having an intake air passage communicating with an air inlet and a blowout air passage communicating with an air outlet that allows air to be blown out in a single direction; a fan; a front heat exchanger facing the air outlet of the housing and including first and second heat exchangers; and at least one of rear and side heat exchangers that face rear and side surfaces of the housing, respectively. When the front heat exchanger operates as a condenser, the first heat exchanger operates as a condenser, and condensed and liquified refrigerant flows in the second heat exchanger. The second heat exchanger is located downstream of the first heat exchanger and the at least one of the rear and side heat exchangers in the flow direction of a refrigerant.

An external-air conditioning apparatus and a ventilation system are provided, the external-air conditioning apparatus includes a fin tube type heat exchanger and a housing that stores this heat exchanger. The housing includes a base body that serves as a back side of the apparatus body and a cover body that serves as a front side of the apparatus body, and the base body and the cover body are dividable and detachable in structure. The base body has a base portion, a partitioning portion, a connecting pipe portion, a heat-exchanger-holding structure portion, and a water receiving portion. The cover body is a structure in which a front wall portion and a three-side peripheral wall portion are formed integrally with each other, and a part in which the peripheral wall portion is not formed is an inlet for external air.

An outdoor unit for a refrigeration cycle apparatus includes: a heat exchanger having an outer surface inclined downward; a drain pan on which the heat exchanger is set; a top frame on which a fan is set, the top frame being disposed at a top of the heat exchanger; and a support attached to the drain pan and the top frame, the support extending between the drain pan and the top frame.

A heat exchanger includes a pipe made of aluminum, a thermistor, and an attaching portion with which the thermistor is attached to the pipe. The pipe carries a flow of refrigerant. The thermistor detects a temperature of the refrigerant. The pipe includes a sacrificial layer provided on a part of a surface of the pipe. The sacrificial layer is lower in potential than the aluminum of the pipe. The attaching portion is higher in potential than the sacrificial layer. At least one part of the attaching portion is attached to the surface of the pipe where the sacrificial layer is not provided. The attaching portion includes a brazed portion that is higher in potential than the sacrificial layer. The thermistor is attached to the pipe with the brazed portion.