The portable electric fire was first invented in the last decade of the 19th century. It consisted of electric radiant panels made of heating elements embedded in enamel in a cast iron plate. However, as the heater warmed up, the enamel and the iron expanded at different rates, causing the elements to break. Shortly after the turn of the century, a new version was developed, using incandescent bulbs to provide the heat, with a reflective back plate to direct the heat forward. However, these too were unsuccessful. The main problem with the electric fire was that the elements lasted only a very short time before burning out. All this changed, however, when in 1906 an element made of an alloy containing nickel and chrome was patented by A.L. Marsh.
Although electric fires were now more reliable, they still did not become popular until the late 1930's when electricity became competitive in price with gas and coal. The next development was the one which made the electric heater more like the ones we have today. Retaining the heating element, an electric motor was added to drive a small fan which would blow the air across the element. This developed into what we now call a portable fan convector.
Today's fan convector has an element wound into a spiral shape behind the front grille of the heater. Air from the room is drawn into the heater through a grille at the top, warmed by the element and then blown out through the front grille. A thermostat controls the air temperature, cutting out the element when the air drawn in reaches the required temperature. A safety cut out isolates the element from the electrical supply if the fan should stop working, otherwise the element would burn out. However, this is still a relatively expensive way of heating and is only normally used as temporary heating, or to heat a room for a short time.
