Convection heater

A convection heater is a heater which operates by air convection currents circulating through the body of the appliance, and across its heating element. This heats up the air, causing it to increase in volume and so become buoyant and rise. Oil heaters are an example of this kind of heating appliance. A convection heater may have an electrical heater element, a hot water coil, or a steam coil. Because of the natural ventilation, they are quieter in operation than fan heaters.

The Model “S”, here as illustrated in 1924, is an example of an early model convection space heater, by the Sala Heater & Mantel Co. in Dallas, Texas. The Model "S" was considered to be highly efficient radiant type of gas heater at the time. The heater utilizes radiant heat, and, by virtue of draft construction, supplements its power by drawing cold air through the facing, heating it and forcing it into the room through the register. This not only forces the circulation that provides an even warmth in every section of the room, but enables the heater to operate at all times with a perfectly cool exterior. Positive circulation provides an even warmth throughout the room, and guarantees a clean, humid, healthful air to occupants.

The mixing chamber, due to its exclusive construction, utilizes centrifugal force to insure a perfect mixture between the gas and air, which in turn provides complete combustion, thus preventing dangerous fumes. After the gas leaves the mixing chamber it passes into a distribution chamber whose shape is such that an equal amount of gas passes into each jet, giving uniform flame height and also intensity.

Due to the rising warm air from convector heaters, warm air may accumulate at the ceiling of the room. Therefore, convector heaters are often paired with ceiling fans, especially in rooms with tall ceilings. In the winter, setting a fan to turn clockwise will allow for more air circulation and will keep heat from rising completely, making the room feel warmer and allowing one to turn down the thermostat.

2. blog.fanimation.com - "5 Myths About Ceiling Fans: Busted"

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Wikipedia