Heat exchanger

Heat exchanger (30), which comprises a thermopositive core part (31) and thermopositive heat transfer elements (32), and in which heat exchanger

• the heat transfer elements (32) are thin and elongated objects, such as wires, bristles, fibers, strips or equivalent,
• the core part (31) comprises at least two compression surfaces or pieces with a compression gap between them where the heat transfer elements (32) are squeezed so as to allow conduction of heat from the compression surfaces or pieces to the heat transfer elements or vice versa,
• the heat transfer elements (32) are so mounted in the compression gap between the compression surfaces or pieces that at least part of the length of the thin wires, bristles, fibers, strips or equivalent of the heat transfer elements remains outside the compression gap, characterized in that
• the core part (31) of the heat exchanger (30) comprises at least one helical elongated body, such as a spiral tube or a rod bent like a helical spring, or two or more bodies, such as tubes or rods, twisted about each other,
• and that the heat transfer elements (32) of the heat exchanger (30), such as wires, bristles, fibers, strips or equivalent, are squeezed between the helices of the helical body or between the bodies twisted about each other.