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While there are different types of furnaces, many heating systems function in the same basic manner. The four main types of furnaces include electric, gas, oil, and solid fuel. While the types of fuel differ, furnace parts tend to be similar. The basic furnace design begins with a thermostat. The thermostat gauges the temperature, which determines when the burner should be ignited.
An ignitor glows to light the burner, which simply put, burns fuel to create heat. More precisely, heated gas from the burner begins to raise the temperature inside the furnace’s heat exchanger. Heat exchangers are dual purpose furnace parts. They warm the air that is then distributed and they keep fumes created by burned fuel separated from the heated air that will be circulated.
Other furnace parts include the blower, which draws air in to be warmed as well as distributing warm air back into the space that needs to be heated. The air is moved through the duct work in each direction, cool air being drawn to the furnace through the return ducts while heated air is moved to the living space through supply ducts. The heated air leaves the duct and reaches the space via openings called vents or heat registers.
The fan limit switch keeps the blower from distributing air until it has been heated to the proper temperature. It also shuts off the burner if the temperature becomes too high. Thus, it prevents the furnace from running more than it needs to as well as acting as a safety feature.
Learning about basic furnace parts can give you the general idea of how a furnace works. Professional assistance is strongly recommended for furnace repair, but knowledge of fundamental furnace parts may be helpful in troubleshooting furnace issues or in performing light maintenance.
Most home furnaces also have a filter. The filter should be cleaned or replaced regularly. This is important not only to keep furnace parts clean and in optimum working order, but also to help filter the air that you breathe.
Another of the basic yet important furnace parts is the pilot light. It is often one of the first furnace parts checked when trouble is reported. Relighting the pilot light may prevent an unnecessary service call. If you don’t know how to light the pilot light, ask the repair person to show you how to do it safely and correctly on his or her next visit.