Abstract: There is provided a convector comprising a plastic tube arranged in the shape of a flattened helix, the major flat sides of which are displaced relative to each other in the axial direction of the helix, such that the bend radius of the tube at the minor sides of the helix is substantially longer than half the distance between the major sides of the flattened helix.The convector can be produced by starting with a supply of plastic tubing, forming a bend in the tube, inserting the bend in a slot in one of a pair of parallel support structures, each having a series of oblique and parallel slots, forming a fresh bend in the tube and inserting the bend in a slot on the other structure, and so on.