“HVAC” Defined

The acronym HVAC (pronounced “H-VAC”) is derived from Heating, Ventilation and Air Conditioning. Add Refrigeration and you get HVACR. For brevity’s sake the general term “HVAC” is used throughout this site.

The field of HVAC is extremely broad and it can’t easily be defined in one paragraph, let alone one sentence, but here’s a primer:

HVAC deals with the air cleaning and conditioning (temperature control) of a so-called “conditioned space.” Conditioned spaces can include residences, office buildings, institutional facilities, supermarkets, restaurants, manufacturing facilities, vehicles for transportation, agricultural facilities, snow-melting systems and for things as obscure as the well pipe heating system devised to facilitate crude oil capture in the oil spill disaster in the Gulf of Mexico.

Heating: System types include, Forced Hot Water (FHW) and Steam – both are “Hydronic”; Forced Hot Air (FHA); Domestic Hot Water and Passive Solar. There are many fuel sources within these types that include, #2 fuel oil and Kerosene; Natural, Liquified Propane, Methane, Butane and other gases; Coal; Geothermal; Electric; Wood; Wood Pellets; Wood Chips; and general Refuse.

Ventilation: System types include, Heat Recovery Ventilation (HRV); Energy Recovery Ventilation (ERV); Direct Ventilation and myriad Exhaust system types.

Air Conditioning (A/C): Typical A/C systems are, Central; “Ductless Split”; High Velocity; Geothermal; Absorption; Direct Expansion (DX) and Swamp Coolers.

Refrigeration: There are 2 genres of refrigeration, Cyclic and Non-Cyclic. The former refers to mechanized equipment that creates a refrigeration cycle utilizing refrigerant in varying states of liquid and vapor. The latter refers to cooling through the melting of ice or sublimation of frozen carbon dioxide (Dry Ice). Cyclic Refrigeration is categorized in 3 temperature ranges: High Temperature, Medium Temperature and Low Temperature.

Indoor Air Quality Control: Standard means for controlling the air quality in a conditioned space are accomplished through, Air Filtration; Ultraviolet Light Illumination; Humidification; Dehumidification and Ionization .