HVAC (pronounced either "H-V-A-C" or "H-vak") is an initialism or acronym that stands for "heating, ventilating, and air conditioning". HVAC is sometimes referred to as climate control and is particularly important in the design of medium to large industrial and office buildings such as skyscrapers and in marine environments such as aquariums, where humidity and temperature must all be closely regulated while maintaining safe and healthy conditions within. In certain regions (e.g., UK) the term "Building Services" is also used, but may also include air conditioning plumbing and electrical systems. Refrigeration is sometimes added to the field's abbreviation as HVAC&R or HVACR, or ventilating is dropped as HACR (such as the designation of HACR-rated circuit breakers).
Heating, ventilating,and air conditioning is based on the principles of thermodynamics, fluid mechanics, and heat transfer, and on inventions and discoveries made by Michael Faraday, Willis Carrier, Reuben Trane, James Joule, William Rankine, Sadi Carnot, and many others. The invention of the components of HVAC systems went hand-in-hand with the industrial air conditioning revolution, and new methods of modernization, air conditioning higher efficiency, and system control are constantly introduced by companies and inventors all over the world.
The three functions of heating, ventilating, and air-conditioning are closely interrelated. All seek to provide thermal comfort, acceptable indoor air quality, and reasonable installation, operation, and maintenance costs. HVAC systems can provide ventilation, reduce air infiltration, and maintain pressure relationships between spaces. How air is delivered to, and removed from spaces is known as room air distribution.[1]
- Related Videos
- Related Articles
- Ask / Related Q&A
- Carrier Air Conditioning Compressor Outlasts Competition
- Houston Air Conditioning
- In a World of Climate Change You Can Keep Yours Constant With Proper Air Conditioning
- Ducted Air Conditioning – Residential Installations
- Get A Professional For Air Conditioning And Heat Installation
- Air Conditioning and Heat Installation Best Left to Experts
- The Purpose of a Cab Mount Air Conditioning Unit
- Air Conditioning Calculator Helps Determine Unit Size




Linn Digital Stream Players - Replace Your CD Player
By: Ivor Davies | 04/01/2010If you are not sure what a digital stream player is how can you possibly tell if owning a DS player will improve your life? Well, a Linn DS player will not make you attractive to the opposite sex, but, it will provide an enhanced quality of sound to your CD and digital music download collections.
What Are The Best Home Coffee Makers?
By: Matt LeClair | 04/01/2010Whether you enjoy coffee in the morning with your breakfast, or with your lunch, or after dinner with your desert, there has become an increasing demand for a coffee maker that is able to create that wonderful drink that you so much enjoy. Because there have been so many advances in technology, there are coffee makers out there that can get the job done for you like never before.
BUXTON PALM WALLET: Palm Sized Organization
By: Katey Kidd | 01/01/2010The Buxton Palm Wallet is a small zippered leather wallet that's divided into compartments for easy storage and retrieval of cards, receipts, etc. One interior compartment contains an fan-out accordion slots for cards, and the other compartment is divided into three areas for item storage.
Why prefer solar lighting?
By: Adam Jackson | 01/01/2010Brief history of tapping solar energy: From times immemorial the importance of solar power as a source of energy has been recognized. In earlier days, reflectors were used for interior lighting during day time. At the same time, day time lighting also involved proper
Six Reasons Your Cat Vomits And What You Can Do
By: Gen Wright | 01/01/2010If you can work out the reason your cat vomits, then you will be able to work out the solution. Here are the most common reasons a cat vomits.
The Razor RipRider 360 is So Awesome its Dizzying
By: Perry Simpson | 31/12/2009The basic scooter design has been stuck at a standstill for a long time, but the Razor RipRider 360 is here to prove three wheels are better than two. Even better, swivel wheels are more fun than fixed wheels.
The Results Are In! - Razor Rip Rider 360 Reviews
By: Perry Simpson | 31/12/2009It only takes a brief survey of the internet to turn up a ton of Razor Rip Rider 360 reviews. Whether you are a Yahoo aficionado, prefer Google, or are a fan of the new Bing, a simple search will turn up all the feedback you need to make an informed decision.
Clean Up With Absorbent Bounty Paper Towels
By: Gen Wright | 31/12/2009Bounty, also known as the "Quicker Picker Upper," is the brand of paper towels preferred by cleaning specialists for superb performance and absorbency. These durable Bounty paper towels clean up spills quickly and are inexpensive enough for everyday use at home or at the office. They hold up to their reputation for toughness but they are still soft to the touch. Soak up small or large spills in every room, especially those in which spills are most likely to occur.
Air Conditioning - Again
By: Andrew | 06/08/2009 | FurnitureAir conditioning and refrigeration are provided through the removal of heat. The definition of cold is the absence of heat and all air conditioning systems work on this basic principle. Heat can be removed through the process of radiation, convection, and conduction using mediums such as water, air, ice, and chemicals referred to as refrigerants. In order to remove heat from something, you simply need to provide a medium that is colder—this is how all air conditioning and refrigeration systems w
Energy efficiency
By: Andrew | 06/08/2009 | Home ImprovementFor the last 20–30 years, manufacturers of HVAC equipment have been making an effort to make the systems they manufacture more efficient. This was originally driven by rising energy costs, and has more recently been driven by increased awareness of environmental issues. In the USA, the EPA (Environmental Protection Agency) has also imposed tighter restrictions. There are several methods for making HVAC systems more efficient. Heating energy Water heating is more efficient for heating buildings
Air Conditioning - Major terms 3
By: Andrew | 02/08/2009 | AccessoriesLouvers Blades, sometimes adjustable, placed in ducts or duct entries to control the volume of air flow. The term may also refer to blades in a rectangular frame placed in doors or walls to permit the movement of air. Makeup air unit (MAU) An air handler that conditions 100% outside air. MAUs are typically used in industrial or commercial settings, or in "once-through" (blower sections that only blow air one-way into the building), "low flow" (air handling systems that blow air at a low
Air Conditioning - Major terms 2
By: Andrew | 02/08/2009 | AccessoriesDamper A plate or gate placed in a duct to control air flow by introducing a constriction in the duct. Deep lake water cooling The heat is rejected to deep lake regions to cool homes and offices, reducing the energy costs. ΔT ΔT (delta T) is a reference to a temperature difference. It is used to describe the difference in temperature of a heating or cooling fluid as it enters and as it leaves a heat transfer device. This term is used in the calculation of coil efficiency. Evaporator
Air Conditioning - Major terms 1
By: Andrew | 02/08/2009 | AccessoriesAir changes per hour (ACH) The number of times per hour that the volume of a specific room or building is supplied or removed from that space by mechanical and natural ventilation. Air handler, or air handling unit (AHU) Central unit consisting of a blower, heating and cooling elements, filter racks or chamber, dampers, humidifier, and other central equipment in direct contact with the airflow. This does not include the ductwork through the building. British thermal unit (BTU) Any of
Air Conditioning - Energy efficiency
By: Andrew | 02/08/2009 | AccessoriesFor the last 20–30 years, manufacturers of HVAC equipment have been making an effort to make the systems they manufacture more efficient. This was originally driven by rising energy costs, and has more recently been driven by increased awareness of environmental issues. In the USA, the EPA (Environmental Protection Agency) has also imposed tighter restrictions. There are several methods for making HVAC systems more efficient. Heating energy Water heating is more efficient for heating buildings
Air Conditioning
By: Andrew | 02/08/2009 | AccessoriesAir conditioning and refrigeration are provided through the removal of heat. The definition of cold is the absence of heat and all air conditioning systems work on this basic principle. Heat can be removed through the process of radiation, convection, and conduction using mediums such as water, air, ice, and chemicals referred to as refrigerants. In order to remove heat from something, you simply need to provide a medium that is colder—this is how all air conditioning and refrigeration systems w
Air Conditioning - Ventilating
By: Andrew | 02/08/2009 | AccessoriesVentilating is the process of "changing" or replacing air in any space to control temperature or remove moisture, air quality in buildings. Methods for ventilating a building may be divided into mechanical/forced and natural types.[3] Ventilation is used to remove u