HVAC Basics: What Is HVAC, and What Does It Stand For?
You may have seen the term “HVAC” in advertisements and articles about air conditioning and heating and wondered what it stands for. HVAC stands for heating, ventilation and air conditioning. These three elements work together to provide a comfortable indoor environment. A properly working HVAC unit regulates temperature, controls humidity and helps keep the indoor air clean.
HVAC is often used to describe ducted, forced-air heating and air conditioning systems. However, the term also applies to other types of systems, including ductless mini-splits and heat pumps. These systems are available for both residential and business use.
In ducted systems, conditioned air is distributed through ducts. Usually, both an air conditioner and furnace are connected to a ducted system. However, depending on the climate in the area where you live, a ducted system may include only a furnace or an air conditioner.
Ductless mini-splits do not require ducts to distribute conditioned air. Instead, indoor blower cassettes are connected to an outdoor condenser by a conduit routed through a small hole in the wall. The conduit contains wiring, refrigerant and condensate lines. Each cassette has its own controls, allowing regulation of temperature in a single room or zone. When a room is not in use, the blower can be turned off without affecting comfort in other rooms.
Heat pumps provide heating and cooling in a single unit. They are used in both forced-air and ductless systems. Heat pumps are energy efficient because they do not use energy to produce heat. Instead, they move heat from one place to another. Electricity is used to power fans, motors and blowers.
There are several types of heat pumps. The most common are air-source systems that extract heat energy from the outside air during winter and route it indoors. Ground-source, or geothermal, heat pumps extract heat energy from the earth. During the summer, both systems operate on the principles of refrigeration by extracting heat from the interior of a building and routing it outside.
Ventilation and Indoor Air Quality
Ventilation brings in fresh outdoor air and expels stale indoor air. This air exchange contributes to good indoor air quality. In addition, HVAC units have air filters that capture airborne particulates. In ducted systems, filters prevent pollutants from entering ducts and the living space. In ductless systems, air is not distributed through ducts, so pollutants are not transferred between rooms.
There are several accessories available that work with HVAC systems to increase ventilation and keep indoor air clean, including humidifiers and dehumidifiers, whole-house ventilation systems, UV lights that kill pathogens and air cleaners.
Licensed HVAC contractors are familiar with these systems and components. Most reliable companies offer repair services, preventive maintenance and new installations. The result is a well-functioning heating and cooling system that keeps humidity and temperatures at comfortable levels. HVAC professionals also analyze indoor air quality and recommend good practices and products to keep the air that you breathe clean and fresh.
For more information, visit a Raleigh, NC HVAC contractor website.