A heat exchanger includes a body defining a flow channel, and a pin extending across the flow channel, the pin including an at least partially non-cylindrical shape. The pin can be a double helix pin including two spiral branches defining a double helix shape. The two branches can include a uniform winding radius. The two branches include a non-uniform winding radius. The non-uniform winding radius can include a base radius and a midpoint radius, wherein the midpoint radius is smaller than the base radius. The two branches can be joined together by one or more cross-members.

To increase a heat exchange capacity of an indoor heat exchanger without increasing a pressure loss inside tubes of an outdoor heat exchanger. A heat exchanger is constituted by an indoor machine equipped with an indoor heat exchanger 10 constituted by a plurality of heat transfer tubes 12A, which have a spiral grooves 13A formed with a predetermined lead angle Ra on inner faces of the tubes and are made to pierce a plurality of fins 11, and an outdoor machine equipped with an outdoor heat exchanger 20 constituted by a plurality of heat transfer tubes 22A which have a lead angle Rb of spiral grooves 23A smaller than that of a heat transfer tubes 10A used for the indoor heat exchanger 10 and are made to pierce a plurality of fins 11.

To increase a heat exchange capacity of an indoor heat exchanger without increasing a pressure loss inside tubes of an outdoor heat exchanger. A heat exchanger is constituted by an indoor machine equipped with an indoor heat exchanger 10 constituted by a plurality of heat transfer tubes 12A, which have a spiral grooves 13A formed with a predetermined lead angle Ra on inner faces of the tubes and are made to pierce a plurality of fins 11, and an outdoor machine equipped with an outdoor heat exchanger 20 constituted by a plurality of heat transfer tubes 22A which have a lead angle Rb of spiral grooves 23A smaller than that of a heat transfer tubes 10A used for the indoor heat exchanger 10 and are made to pierce a plurality of fins 11.

A heat exchanger includes a heat transfer member that includes a first main surface and a second main surface. The first main surface is disposed to face a flow channel for a cooling fluid. The first main surface includes a plurality of is provided with protrusions that extend in a direction perpendicular to a flow direction of the cooling fluid. The second main surface is flat. The protrusions have an undulating profile in plan view, and undulating convex portions have an apex angle of facing opposite to the flow direction of the cooling fluid is greater than 105 and less than 180. The cooling fluid flowing through the flow channel of the heat exchanger is an aqueous solution having a laminar flow.

A heat exchanger is constituted by an indoor machine equipped with an indoor heat exchanger constituted by a plurality of heat transfer tubes, which have spiral grooves formed with a predetermined lead angle on inner faces of the tubes and are made to pierce a plurality of fins, and an outdoor machine equipped with an outdoor heat exchanger constituted by a plurality of heat transfer tubes which have a lead angle of spiral grooves smaller than that of a heat transfer tubes used for the indoor heat exchanger and are made to pierce a plurality of fins.

To increase a heat exchange capacity of an indoor heat exchanger without increasing a pressure loss inside tubes of an outdoor heat exchanger. A heat exchanger is constituted by an indoor machine equipped with an indoor heat exchanger 10 constituted by a plurality of heat transfer tubes 12A, which have a spiral grooves 13A formed with a predetermined lead angle Ra on inner faces of the tubes and are made to pierce a plurality of fins 11, and an outdoor machine equipped with an outdoor heat exchanger 20 constituted by a plurality of heat transfer tubes 22A which have a lead angle Rb of spiral grooves 23A smaller than that of a heat transfer tubes 10A used for the indoor heat exchanger 10 and are made to pierce a plurality of fins 11.

Apparatus for rapid heating of a liquid including a heat source, a liquid flowpath defining element defining a liquid heating flowpath therein having a liquid inlet and a liquid outlet, a collection of flexible elongate thermal conductors located within the flowpath, the collection of flexible elongate thermal conductor portions being thermally coupled to the heat source and defining multiple liquid heating passageways through the flowpath whose configurations and cross-sectional dimensions change over time, thereby being resistant to clogging.

To increase a heat exchange capacity of an indoor heat exchanger without increasing a pressure loss inside tubes of an outdoor heat exchanger. A heat exchanger is constituted by an indoor machine equipped with an indoor heat exchanger 10 constituted by a plurality of heat transfer tubes 12A, which have a spiral grooves 13A formed with a predetermined lead angle Ra on inner faces of the tubes and are made to pierce a plurality of fins 11, and an outdoor machine equipped with an outdoor heat exchanger 20 constituted by a plurality of heat transfer tubes 22A which have a lead angle Rb of spiral grooves 23A smaller than that of a heat transfer tubes 10A used for the indoor heat exchanger 10 and are made to pierce a plurality of fins 11.

A thermally conductive pipe includes a pipe of which both end portions are closed, a working liquid that is sealed inside the pipe and vaporizes and liquefies, and a liquid transfer unit that exists along a longitudinal direction inside the pipe and transfers the liquefied working liquid at least in the longitudinal direction, in which the liquid transfer unit has, in a case of being viewed in a cross section of the pipe, which is orthogonal to the longitudinal direction, a first liquid transfer unit that is in contact with at least a partial range of an inner wall surface of the pipe and a second liquid transfer unit that is not in contact with the inner wall surface of the pipe and the first liquid transfer unit.