What Is an HVAC System?

Michael Johnson

HVAC is an abbreviation for Heating, Ventilation and Air Conditioning. HVAC systems are the main mechanical infrastructure of a building and provide climate control functions. An HVAC system can range from a compact unit placed in a window sill to a multisystem unit that is installed on a roof or in a basement. HVAC systems are typically the most costly elements of construction. Aside from a compact unit, HVAC costs can amount to as much as 25 percent of a new building's construction costs.


An HVAC system has the ability to pump hot, cold or fresh air into an area. It pulls fresh air from the outside and then alters it to the desired temperature. Often HVAC systems use hot or cold water to either chill or heat the air. The air passes over coils filled with the chilled/heated water and thus absorbs the temperature.


HVAC systems can range from the size of a 2-by-2 foot box placed in your window to a multitude of units covering a building's roof and weighing many tons. The size of the HVAC system directly affects its capacity. The larger the unit, the more capacity it has to produce climate-controlled airflow. This more airflow a unit can produce, the larger a space it can adequately condition.


HVAC units have greatly improved the quality of life for people. Aside from being able to climate-control facilities in extreme temperature regions (such as Alaska in winter or Texas in summer), HVAC plays a large role in industry. Food transport, chemical storage and medicinal development are all dependent on HVAC systems to achieve the temperature necessary for their products not to spoil.


HVAC systems may be pleasant for your indoor habitat, but they are tremendous users of energy. They lead to high-energy costs and take a toll on the environment. It is reported that 60 percent of all commercial and residential energy use in the United States is related to HVAC systems. When possible, other alternatives (such as opening a window or installing shades) should be considered before relying on a HVAC system to produce the desired temperature.


The main benefit of an HVAC system is comfort. HVAC systems allow people to function even when the most adverse weather conditions occur outside. Prior to HVAC systems, office productivity was greatly affected by the climate. Employees are not suited to do their best work in extreme heat or cold. HVAC provides a solution by always maintaining a constant temperature for a building.