Commonly, there are two types of heaters according to the power source. One is the gas heater which uses burnt gas for heat production. In the case of electric heaters, electricity is passed through a resistant conductor like those of coils and metal wires. The conductor then breaks up the energy from the current as heat.
The two kinds of gas heaters are the vented and the unvented gas heaters. The vented gas heaters are connected to a passageway which is covered. The two ducts either bring the air in from outside and the counterpart takes out the exhaust fumes. This is considered the safest form of gas heater. On the other hand, unvented gas heaters are intended used for outdoors, because it directly emits the fumes.
In the case of electric heaters, they do not produce fumes. This would assure the safety of those in the room. Heat is not wasted by the means of passing through a flue.
There are three common types of electric heaters. The micathermic heater warms the air within a cavity and it depends on natural convection for distribution. Secondly, ceramic heaters make use of a hot ceramic disc alongside a fan air air distribution. The convection heaters can be operational with or without fans. They use an electric coil found in a chamber filled with oil. Its appearance resembles with that of a central-heating radiator.
Prices of these heaters could range from about 20 USD up to 50 USD.