Central heating System
A central heating system provides warmth to the whole interior of a building (or portion of a building) from one point to multiple rooms. When combined with other systems in order to control the building climate, the whole system may be a HVAC (heating, ventilation and air conditioning) system.
Central heating differs from local heating in that the heat generation occurs in one place, such as a furnace room in a house or a mechanical room in a large building (though not necessarily at the “central” geometric point). The most common method of heat generation involves the combustion of fossil fuel in a furnace or boiler. The resultant heat then gets distributed: typically by forced-air through ductwork, by water circulating through pipes, or by steam fed through pipes. Increasingly, buildings utilize solar-powered heat sources, in which case the distribution system normally uses water circulation.
How Central Heating Systems Work
- A furnace works to keep a home warm in the winter and plays a critical part in the operation of an air conditioning system.
- Furnaces produce heat through the combustion of natural gas in the furnace’s burner. The heat produced from this process then passes through a heat exchanger. Air from your home’s return air ducts is blown over the heat exchanger, thus warming the air.
- The furnace’s blower then blows the warmed air into the duct-work, which carries and disperses the warmed air throughout the home.
- During warmer months, the blower inside a furnace continues to circulate return air throughout the home–only this time, the return air has been cooled by being blown over the indoor coil portion of the home’s split-system air conditioning system. The condensing coil is typically installed on top of the furnace.
- Indoor warmth any time it is required.
- Energy efficiency – The efficiency of a furnace can be determined by its AFUE – or Annual Fuel Utilization Efficiency. The minimum efficiency level for furnaces currently manufactured in the U.S. is 80% AFUE. A rating of “80% AFUE” means that for every dollar you spend heating your home; 80 cents are actually applied to the generation of warmth. Compared to many of the 60% AFUE furnaces in older homes, 80% AFUE furnaces are a significant improvement. However, for enhanced energy efficiency, you may wish to consider a 95+% AFUE furnace, such as Amana’s line of 96% AFUE Furnaces.
- Cleaner air – As your HVAC system draws air out of various rooms in the house through return air ducts, the air is pulled through an air filter, which removes airborne particles such as dust and lint. Sophisticated filters may remove microscopic pollutants, as well. The filtered air is then routed to air supply duct-work that carries it back to rooms. Whenever the HVAC system is running, this cycle repeats continually, constantly filtering and cleaning the air in your home.