How Do Furnaces Work?

Carrier FurnaceOlder heating systems are mostly furnaces. During the earlier years, people used to fuel their furnaces with coal and wood. In the modern day, residential furnaces are run by electricity, gas or even propane and operate at high-efficiency rates. But how exactly do they work?

The Principle of Forced Air Heating

All furnaces, despite the fuel they use, operate on the forced air heating mechanism. You see, the furnace heats air, then blower fans circulate the warmed air throughout the duct system and air vents of a house. In most cases, furnaces use the same duct system as the air conditioner, therefore there is no need to look for extra space for your cooling system.

Electric Furnace

Instead of using a pilot light like a gas furnace, an electric furnace uses an electrical ignition to start the heating process. The electrical ignition ignites heating elements with conductive coils. Current passes through these coils, and they start to heat the air, which is then circulated by the blowers. The heating is regulated by the thermostat.

Gas Furnace

In a gas furnace, a pilot light is used to ignite several burners found in the combustion chamber. The burners produce heat which goes into the heat exchanger, where the air is warmed up to the temperature set on the thermostat. From here, the blower fans take the warmed air and distribute it throughout the air ducts. A furnace fueled by propane uses a similar mechanism.

Diagnosis of Furnaces

Furnaces have a lot of parts that make sure that heat exchange and circulation takes place well without any safety issues. Trying to diagnose or remedy a problematic thermostat alone is not wise unless you have undergone complete HVAC training and have the necessary tools. If you do not know how to fix the problems in your furnace, you should call experts to deal with the malfunctions in your furnace, no matter what fuels it. Gas furnaces have been known to cause carbon monoxide poisoning, and electric ones can lead to electrical shocks, so it is important to have a qualified HVAC technician to regularly diagnose the status of your furnace.