How a Boiler Works
The boiler usually sits on top of a burner in which fuel is burned to produce heat. The fuel produces the heat, the water or steam in the boiler is used to distribute the heat through the house usually via pipes and radiators.
The most common fuel for boilers in the United States today is natural gas which is usually piped directly into the house from a pipeline that runs under the street or road. In rural areas not served by natural gas lines the most common fuel for boilers is propane gas which is kept in a large tank in the yard and piped into the house. Propane is usually more expensive than natural gas.
In some areas of the US mainly New England there are some boilers that are heated by fuel or heating oil. Outside of the Northeast oil fired boilers are actually very rare. Many oil fired boilers have been converted to burn natural gas or propane. The reason natural gas and propane are more popular is that they are much cheaper fuels.
There are also a small number of boilers around that burn other fuels. Before Word War II many boilers burnt coal. Today, some people particularly in rural areas burn wood because it is often cheaper than natural gas or propane. There are also boilers that burn other more exotic fuels such as waste oil, wood pellets and even corn cobs.
Boilers and Forced Air Heating
Something to keep in mind is that most homes in the United States do not use a boiler for heat. Most American and Canadian homes are heated via forced air in which a device called a furnace heats air that is blown through the house to provide heat.
The cost of operating a forced air heating system and operating a boiler is pretty much the same but forced air heating systems are usually cheaper to install. Forced air heating is cheaper because it doesn’t require the installation of a network of pipes and radiators to distribute heat to the house.Many people will confuse boilers with forced air furnaces because both devices usually sit in the basement and use the same kinds of fuel. Boilers are more common in colder areas because they can provide more heat.