Forced-air furnaces are among the more common heating systems installed in American homes. They get their name from the fact that the system literally “forces” warm air from the furnace to your living spaces. The following information will help you better understand how forced-air furnace technology works.
There are five main components of a forced-air heating system:
- Thermostat: Allows you to set the temperature levels for your home. Senses indoor temperatures and controls furnace operation.
- Furnace unit: The main unit where air is heated. It may contain fuel-consuming burners or electric coils for generation of heat.
- Blower or air handler: A powerful fan that forces heated air out of the furnace unit, through the supply ductwork and into your home.
- Supply ductwork: A network of large metal pipes that carries heated air from the furnace to your home.
- Return ductwork: Sometimes called cold-air ducts or duct returns, these pipes bring cooled air back to the furnace to be filtered, heated and redistributed.
To begin a heating cycle, the desired indoor temperature is set at the thermostat. When indoor temperatures fall below that level, the thermostat switches on the furnace. Controlled flames or heating coils inside the furnace unit produce heat that is transferred to a heat exchanger.
A blower fan sends air across the heat exchanger. The air absorbs the heat and is warmed to a usable temperature. The blower forces the air into the supply ductwork. The warm air travels the length of the ductwork and exits from openings at the far end of the duct system. The air enters your home and raises indoor temperatures.
After the heat is expended, the return ductwork brings air back into the system to be filtered, reheated and circulated again. The heating cycle continues until the thermostat detects indoor temperatures that match the unit’s temperature settings. The furnace shuts off until temperatures drop, and the heating cycle begins again.
In business since 1974, Jackson & Sons serves heating and cooling customers throughout eastern North Carolina. Contact us today for more information on forced-air furnace technology or to see a full line of furnaces that can meet your home comfort needs.
Our goal is to help educate our customers in Eastern North Carolina (including Wayne, Johnston, Greene, Lenoir, and Duplin Counties) about energy and home comfort issues (specific to HVAC systems). For more information about forced-air furnaces and other HVAC topics, download our free Home Comfort Resource guide.
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