Forced air heating is when air is heated and distributed through a home using ducts.
The air can be heated by a gas furnace, an electric furnace, or a heat pump, and when a fan is put into the system air is forced through a home, heating it.
What Does Forced Air Heating Mean in a House?
A home with forced air heating will have warm air blown in through ducts and vents.
A blower motor that is attached to a furnace or heat pump will blow air into a home and warm it.
What Type of Heating System Do you Have?
A heat pump is an air conditioner unit that works in reverse during the winter.
If you have a heat pump, then you don’t use a furnace to heat your home.
A heat pump heats a home during the winter and then reverses to cool a home during the summer.
Furnaces use gas to heat a home, and with most homeowners by far use gas furnaces over heat pumps.
How Does a Forced Air Furnace Work?
Most home furnaces use natural gas that is piped in from a gas company. For homes that can not receive natural gas, propane is used and trucked in manually to a holding tank for a furnace to use.
The gas burners burn a flame in what is called a heat exchanger. When gas burns, it puts out toxic gases such as carbon monoxide, which cannot be circulated through a home.
To do this, a heat exchanger is used to separate the toxic gasses and the air as it flows through a home.
A heat exchanger is made of metal tubes that heat up as a flame burns inside them. The tubes send the toxic gasses out the roof through a vent pipe. The air that passes over the outside of the tubes becomes heated without mixing with the bad gases inside of it.
A fan called a blower motor pulls air into a furnace and pushes it out vents in the home; as it does this, the air passes over the heat exchanger, becoming heated.
Air is pulled into a unit at what is called a Return that has a filter to keep dust and other contaminants from entering the system.
The air will continue to cycle from the vents to the Return and pass the heat exchanger until a switch turns it off.
Thermostats are switches designed to turn on or off a furnace as needed.
A furnace is rated by the BTU or British Thermal Unit. A BTU is the amount of energy needed to raise the temperature of a gallon of water by 1 degree.
Most furnaces are rated to put out between 40,000 and 130,000 BTU depending on the need of a home; which includes the size of the home, how well insulated a home is, and the severity of the winters.