Disclosed is a double wave fin plate for a fin-tube heat exchanger, having: one half-plate having one perimeter edge with one cut-out forming one portion of a tube connector; another half-plate having another perimeter edge with another cut-out forming another portion of the tube connector; the one perimeter edge and the other perimeter edge are connected to one another about each cut-out to form the fin plate and the tube connector; one surface waveform is formed on the one half-plate; another surface waveform is formed on the other half-plate, and the one surface waveform is disposed at an angle to the other surface waveform in the fin plate.

A flat heat transfer tube is used for a cross fin tube type heat exchanger including the flat heat transfer tube having a bending portion and a plurality of holes extending in a direction parallel with an axis direction of the flat heat transfer tube, and a plurality of plate fins bonded by welding to the flat heat transfer tube, wherein an interval between an outer surface of the flat heat transfer tube and an inner surface of the hole of a portion which is curved with a small curvature during bending is larger than an interval between an outer surface of the flat heat transfer tube and an inner surface of the hole of a portion which is curved with a large curvature during bending in a cross section of a portion of the flat heat transfer tube which corresponds to the bending portion before bending.

A refrigerator may include a cabinet defining a low-temperature storage space and a machine chamber in which a compressor and a condenser are disposed; and an evaporator disposed in rear of the storage space, wherein air flows upwards along the evaporator and thus cools down to lower a temperature of the storage space. The evaporator may include a cooling pipe in and along which refrigerant flows; and a plurality of cooling fins surrounding an outer face of the cooling pipe. The cooling pipe may be constructed so that the refrigerant flows downward along and in the cooling pipe.

A cylindrical header of a heat exchanger includes a central member, front-side and rear-side members extending longitudinally on front and rear sides of the central member to form front-side and rear-side spaces along with the central member. The central member has a first flange covering a front-side-member-first-end part and a rear-side-member-first-end part from outside when viewed in cross-section, and a second flange covering a front-side-member-second-end part and a rear-side-member-second-end part from outside when viewed in cross-section. The front-side member is joined to the central member with the front-side-member-first-end part facing an inner surface of the first flange, and the front-side-member-second-end part facing an inner surface of the second flange. The rear-side is joined to the central member with the rear-side-member-first-end part facing an inner surface of the first flange, and the rear-side-member-second-end part facing an inner surface of the second flange.

An air conditioner includes: a first refrigerant tube that includes a first portion, and through which a liquid refrigerant flows; and a second refrigerant tube that includes a second portion that is disposed above the first portion and overlaps the first portion when viewed vertically, and through which a liquid refrigerant flows. The first portion is surrounded with a first heat insulating material.

A heat transfer tube includes first flow paths aligned in the heat transfer tube. Each of the first flow paths includes a section with a rectangular shape that is elongated in a first direction parallel with an alignment direction of the first flow paths. Each of the first flow paths includes protrusions disposed on an inner surface. The section of each of the first flow paths has a long side having a first length and a short side having a second length, where a ratio of the first length to the second length is between 1.1 and 1.5.

A method for manufacturing a heat exchanger is provided. The heat exchanger includes a plurality of plate-like fins that are stacked with a predetermined fin pitch, and a plurality of flat heat exchanger tubes that are disposed with a predetermined spacing from one another along the longitudinal direction of the plate-like fins and extend through the plate-like fins along the stacking direction. The plate-like fins each have a plurality of notches provided in an end portion along the long side. The plate-like fins have a shape corresponding to the cross-sectional shape of the flat heat exchanger tubes, and the flat heat exchanger tubes are inserted into the notches. The manufacturing method includes disposing the flat heat exchanger tubes with a predetermined spacing from one another, and attaching the plate-like fins to the flat heat exchanger tubes one by one by inserting the flat heat exchanger tubes into the notches of each of the plate-like fins.

A fin for a finned pack for heat exchangers, includes a plate in which a plurality of through holes is made for the positioning of tubes to convey a first heat exchange fluid, the plate having an edge as well as two main faces each to be contacted by a second heat exchange fluid in a crossing direction from an inlet portion to an outlet portion of the edge of the plate.

An evaporator for a cooling system has a slab coil having a plurality of refrigerant circuits with each refrigerant circuit being a fin-and-tube assembly that extends across the slab coil. At least one of the refrigerant circuits has a mini-slab circuit extender that has a fin-and-tube assembly that extends across only a portion of the fin-and-tube assembly of that refrigerant circuit and is disposed in front of that portion of the fin-and-tube assembly of that refrigerant circuit.