The HVAC industry mainly deals with air conditioning, heating and ventilation within large buildings and systems. In the more recent years, architectural designs of modern buildings include the operation and maintenance of heating systems that include HVAC equipement such as duct heating, boilers, flanged heaters as well as sophisticated controls. There are several different types of heating systems today. Central heating is common in northern climates to provide comfort heating to residential and commercial units. Typically, these buildings include boilers, furnaces or heat pumps that circulate water, steam or air along arteries of a circulation system that use centrally located units (furnaces) as the central heating location.

Wattco duct heaters are used in duct work that are used in forced air systems to help maintain target comfort  temperatures. Piping is also used to circulate water throughout the 'circulatory system' of a heating unit and reach target temperatures. Other more sophisticated systems use glycol liquids that have a unique property of not solidifying or freezing in low temperatures, throughout piping that acts as a conduit of heat transfer throughout the heating system. Radiators which are mounted on walls or floors, use the circulated liquid and eminate heat throught the room. Boiler systems use Wattco flanged heaters to heat up water or generate steam to heat up large areas.  Heat exchangers can also be involved as secondary heat source when water passes through the first circuit.

Forced air systems use fans that push air through ductwork that pass throughout the building. Often using fin tubular elements or coiled elements, they are extremely effective to help reduce condensation that can result from areas of high humidity. Forced air can also use filters to help purify indoor air.