There are three main types of home heating furnaces available: electric, forced air system, and forced hot water system. Electric furnaces heat loops located in each room of the house to deliver heat into the rooms. They do not use a burner or blower. Forced hot water furnaces use a pump to move water that has been heated by the burner to the rooms of a house, where radiators disperse the heat thou out the room.
Forced air furnaces are different in that they use a furnace blower to move and circulate the hot air through the house via ducts and registers. The main parts of this type of furnace are the burner, plenum, and the blower. The furnace uses oil, gas, or wood to heat the air. Then the heated air accumulates in the plenum and then is blown to the entire house by the work of the furnace blower.
This system has both Pros and Cons.
Pro Forced air furnaces can heat a room or house very quickly. The blower fills the house with warm air, this warm air in turn warms the occupants. Making everyone happy.
Con A forced air system warms the air while the blower is pushing hot air into the room, once the blower shuts off no further heating takes place. While a hot water system also known as a boiler uses pipes and radiators filled with hot water to heat a home. These pipes and radiators remain filled with hot water even after the furnace has shut off, keeping the house warm.
Due to the furnace blower, forced hot air is the fastest way to heat a home. It is somewhat more dangerous due to the possibility of carbon monoxide buildup so it’s important to have a carbon monoxide detector in your home. It is one of the most common furnaces found in homes today.
Most all furnaces work in the same manner. There is a thermostat in the main living area of the home that controls the furnace. When the temperature drops below a preset level, it sends a signal to the burner to begin heating the air. This hot air is then delivered through the house. Once the home has been heated to the preset temperature, the thermostat shuts the burner off. In a furnace with a blower, the blower will continue to work for a few extra minutes after the thermostat tells it to shut off. This is for efficiency using all the heat that was just produced by the furnace.
As you might imagine, the blower is the hardest working part of the furnace. If a furnace stops working, it is frequently the blower that has broken. The furnace blower can be fixed or replaced without having to replace the entire furnace. Older furnaces use a blower with a belt drive which means it is more likely to break. Newer furnaces use a blower that does not use a belt and less likely to break.