How Does an Electric Heating System Work?

Components of Electric Heating

Electric heaters are generally heaters plugged into a wall socket. They're not very complicated. Basically, they're made up of a heating coil or element, possibly a fan or parabolic mirror to distribute the heat, and a unit for collecting energy that plugs into your wall and makes a completed circuit. This allows the heater to draw energy from your wall socket.

Basis of an Electric Heater: The Heating Coil

The heating coil is generally a very low-gauge wire wrapped back and forth that has a resistor on it. A resistor is an electric component made of wire wrapped around something with a very large amount of ohms, which measure electrical resistance. Many resistors are wires wrapped around a solid mixture of carbon dust and ceramics or resin, along with a plastic coating to hold it all together. These resistors serve to inhibit electrical flow through the wires of the heating coil. The resisting qualities of a heating coil are given by resistance wire, which has a high resistance from being low-gauge and is made of alloys that are highly resistant, such as nickel chrome alloys.

Converting Electrical Energy to Thermal Energy

Joule heating states that the heat produced from a wire is proportional to the resistance of a wire, multiplied by the square of the electrical current of the wire. This means that as the resistance and current of a wire rise, the heat emitted will also rise. Because the resistor of an electric heating coil has an incredibly high resistance, even the relatively low amperage from the wall socket from your home is enough to cause the coil to radiate large amounts of heat. A very easy way of understanding this is by making a connection from the heater to water flowing through pipes. As the water (electricity) flows through the pipes (the coil), the resistor keeps the water in the pipes, causing pressure to build. Eventually, as the pressure builds high enough, the water seeps out of the pipes and is released into the outside world, as if the pipes were semi-permeable at high pressures. The released water is analogous to the heat released by the wires.

Dispersing the Heat

The heat created by the electric heater can be diffused across space in many ways. Fans can be used to disperse the hot air caused by the heating coil. Also, the heated air often causes a convention current in an area which, because of the nature of a convection current, disperses the heat across a large area.