Heating appliances specially designed to create a circulating movement of warmed air are called convection heaters because they operate by using convection currents of air.
When air is heated it becomes less dense and, therefore, duty rises and is replaced by cold air.
Convector heaters consist, basically, of metal cabinets with openings at the top and bottom to produce and direct this flow of rising warm air. At the base of this cabinet there is a heating element and this warms the air within the cabinet.
This warm air rises and, as it rises and, as it rises cold air is drawn into the convector from the bottom of the appliance. The cabinet of the convector acts as a flue or chimney and creates a continuous current of warm air.
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