To survive extremely cold winters, people inhabiting parts of the world – away from the tropics towards earth’s poles – use various sources, appliances and techniques to keep themselves warm and comfortable. One of such space heating systems is an electric furnace. Electric furnaces are easier and cleaner to operate when compared to coal, wood, or fossil fuel based furnaces.
Electric Furnace
Herewith a short description on the working of an electric furnace which is an important appliance used to keep homes warm in cold countries.
An electric furnace is basically used to keep houses and other buildings warm by blowing warm air into the space inside. This is done with the help of a blower fan that blows warm air from the electric furnace into a building. The temperature of the warm air being blown inside can be controlled through a thermostat.
Mechanism
Thermostat is a simple electrical appliance that is used to sense and measure temperature, though differently than a clinical thermometer.
When the air temperature inside the space falls below the preset temperature, the thermostat springs into action and switches on the heating coil and the blower of the electric furnace, generally housed either outside or under the house. A heating coil is nothing but a wire made of resistive material that is coiled and spaced closely to pack sufficient length into a small space. Electric current when passed through this coil of resistive wire generates considerable heat uniformly across the length of the wire. This heats up the air inside the furnace, which is then blown into the house or the building with the help of a blower fan to keep it comfortably warm.
This sets the air in circulation – the furnace sucks relatively colder air from outside the furnace, this air gets heated up and is blown into the house. Thus, the entire space begins to warm up, and so does the air feeding the furnace. This is an energy efficient practice where heated air is being re-circulated, and it helps to bring down the monthly electricity bill. In order to keep the air inside the house or building fresh, outside air can also be used. However, the outside air being cold enough cannot be warmed up in a single pass over the coil, and the furnace needs to work longer to bring the temperatures to comfortable levels, thus increasing the energy consumption.
When the air inside is sufficiently warm, the thermostat shuts off the electric furnace until the temperature again falls below the preset level. The cycle thus continues.
To conclude, an electric furnace is the most efficient, clean, non-polluting and economical space heating appliance. It operation and temperature regulation is easier than its alternatives like coal, wood or fossil fuel based furnaces. Moreover, because it is electric, it can be subjected to modern electronic control and automation which can greatly help in optimizing its use and making electric furnaces more energy efficient.
