What does HVAC stand for?
While the Energy Center usually tries to avoid the use of acronyms, HVAC is in common use in the heating and cooling industry. It stands for "heating, ventilation and air conditioning," three functions often combined into one system in today's modern homes and buildings. Warmed or cooled or dehumidified air flows through a series of tubes - called ducts - to be distributed to all the rooms of your house. A central HVAC system is the most quiet and convenient way to cool an entire home.
Unless you live in an amazingly temperate climate, the HVAC system in your home uses more energy and drains more energy dollars than any other system in your home. Typically, 44 percent of your utility bill goes for heating and cooling.
Like many other appliances, HVAC systems have improved in energy efficiency in the last decade. As a result, you can save money and increase your comfort by properly maintaining and upgrading your HVAC equipment.

Who is an HVAC technician?
An HVAC technician is a professional that labors in the field of heating, ventilation, air conditioning service and support. He or she can both install and repair systems, as well as maintaining them. He or she may work as an independent contractor or be employed by a company that specializes in climate control solutions for businesses and residential properties.
When an HVAC technician is associated with the installation of a new system, he or she will be proficient in reading blueprints connected to the installation, and will participate in the preparation of the space for the installation of the required equipment. This may also include the ductwork construction and installation as well as the main components for the system. The HVAV technician will be responsible for making sure the installation is conducted in compliance with local regulations, and that the unit will provide efficient heating and air conditioning for the space.
Depending on the task, HVAC technicians use many different tools. For example, they often use screwdrivers, wrenches, pipe cutters and other basic hand tools when installing systems. To test or install complex system components, technicians may use more sophisticated tools, such as carbon monoxide testers, voltmeters, combustion analyzers, and acetylene torches. When working on air conditioning and refrigeration systems, technicians must follow government regulations regarding the conservation, recovery, and recycling of refrigerants. This often entails proper handling and disposal of fluids.
Some HVAC technicians sell service contracts to their clients, providing regular maintenance of heating and cooling systems. Other craft workers sometimes help install or repair cooling and heating systems. For example, on a large air conditioning installation job, especially one in which workers are covered by union contracts, ductwork might be done by sheet metal workers and duct installers, or electrical work by electricians. In addition, home appliance repairers usually service window air conditioners and household refrigerators.

How much cooling capacity do i need?
Cooling Capacity
Cooling capacity should be your first consideration before buying a window AC. Cooling power is measured in British Thermal Units, or BTUs, per hour–the basic measure of thermal energy. For the best efficiency and effectiveness, stick with a unit that has a BTU level designed to fit your space. A window AC with too little BTU power will run continuously to try to cool a large space and, in the process, will eat up your energy budget. A window AC that's too large for your space won't cool and dehumidify your space evenly, leaving your room air susceptible to uncomfortable hot and cold pockets.
To find your ideal cooling capacity, calculate the size of the space you want cooled in square feet. Then use the chart below to find the right amount of BTUs.
Area To Be Cooled (Sq. Ft.)
Capacity Needed (BTUs Per Hour)
100 to 150 sq. ft. - 5,000 BTUs
150 to 250 sq. ft.. - 6,000 BTUs
250 to 300 sq. ft.. - 7,000 BTUs
300 to 350 sq. ft.. - 8,000 BTUs
350 to 400 sq. ft.. - 9,000 BTUs
400 to 450 sq. ft.. - 10,000 BTUs
450 to 550 sq. ft.. - 12,000 BTUs
550 to 700 sq. ft.. - 14,000 BTUs
700 to 1,000 sq. ft.. - 18,000 BTUs
1,000 to 1,200 sq. ft.. - 21,000 BTUs
1,200 to 1,400 sq. ft.. - 23,000 BTUs
Ideally it is recommended to ask your local hvac technician to provide you with a detailed estimate based on your needs and location.