PURPOSE: To enhance drafting effect and enlarge air flow quantity, by a method wherein each heating element extending vertically is surrounded by a heat- radiating pipe having an intake port opened at its lower end and a discharging port opened at its upper end, and a part of the heating element and a part of the pipe are brought into close contact with each other.

CONSTITUTION: A plurality of heating elements 1 extending vertically are provided in parallel to each other, and each of the elements 1 is surrounded over the substantially entire length thereof by each of a plurality of heat-radiating pipes 4 having the intake port 2 opened at the lower end thereof and the discharging port 3 at the upper end thereof so that air taken in through the port 2 and flowing through the pipe 4 is heated and is discharged through the port 3 by the effect of an upward air flow. A part of the outside peripheral surface of the heating element 1 is brought into close contact with a part of the inside peripheral surface of the pipe 4. Accordingly, the length of the heater in the vertical direction can be set to be larger, a drafting effect can be enhanced, the air flow quantity can be enlarged, and a large quantity of hot air can be provided. Consequently, a room can be heated quickly, and the temperature difference between upper and lower parts of the interior of the room can be reduced.