What is Forced Air Heating?

By | November 10, 2022

how a furnace works
Chances are you have heard the term forced air heating, but what is forced air heating?

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?

What Type of Heating System Do you Have
Modern homes use either a furnace or heat pump to heat the air.

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?

How Does a Forced Air Furnace Work
Gas burners are used to supply the heat, with most using natural gas and sometimes propane.

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.
furnace gas burners
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.
furnace Heat exchanger

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.

Category: Furnace repair

About Aaron H. Benetti

Aaron H. Benetti has worked in the HVAC field since 1991. He began his career as an HVAC installer and later began doing troubleshooting and repairs. Around 2010, he began to write books on HVAC topics, mainly tutorials and how-to information. Currently, Aaron writes many articles and posts for websites as well as books and videos on HVAC topics.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.