HVAC fuel sources
There are three common fuel sources that feed HVAC systems: electricity, natural gas, and oil. Electricity is required by all HVAC systems, and is a highly effective heating source. Oil can be used to heat water or air, but may not be the most cost-effective fuel. Natural gas is a popular energy source used to power kitchen appliances and furnaces. Currently, many homeowners are switching form oil to gas because of perceived economical and environmental benefits. Newer energy sources like geothermal and solar are on the rise for their energy-efficiency potential, though they require more money initially to use.
Air conditioners
Air conditioners can either be connected to a network of ducts or be freestanding, and essentially remove heat from the ambient air, thus cooling it down. In a nutshell, central AC units are composed of an evaporator, a condenser, and a compressor, and use a liquid refrigerant that changes from a liquid state to a gaseous state and back to a liquid state as it cycles through each units’ major structures. Air conditioners also improve indoor air quality by using a washable or disposable filter medium that filter out mold spores, odors, free-floating viruses, dust, pet dander, and other allergens from your home’s air.
Heat pumps and gravity furnaces
Heat pumps utilize electricity to move heat from one area to another. For example, during hotter months, heat pumps move heat from the relatively cooler air inside your home out to mingle with the warm air outside. Since they do not use energy to heat or cool, heat pumps are energy efficient. Gravity pumps, which have mainly been replaced by heat pumps, function on the fact that hot air rises whereas cold air sinks.