The ABC’s of HVAC
Understanding the Terms of the Trade
The heating, ventilation, and air conditioning (HVAC) industry is filled with terms, organizations, and measurements that most people are unfamiliar with. To help you stay informed and empower you regarding one of your most important home utilities, we’ve developed a small dictionary for your convenience!
The machinery and system that controls the temperature and humidity of your home. It also controls the flow of air in your rooms while filtering out impurities.
The Annual Fuel Efficiency Ratio. This measures the ration between the fuel you use and the energy you receive on a yearly basis.
The Air Conditioning and Refrigeration Institute, which sponsors and administrates the certification programs that ensure industry products perform as they are supposed to.
The American Society of Heating, Refrigeration, and Air Conditioning Engineers.
British Thermal Unit, or a unit that measures the cooling and heating capacity of HVAC systems and the cooling and heating needs of a structure (e.g. home, apartment, office building).
The heat transfer rate of HVAC systems per hour, or British Thermal Units per Hour.
Refers to an air conditioner or heater’s ability to effectively cool or heat a space. Capacity is usually measured in BTUs or tons.
The equipment that pumps refrigerant through the air conditioner lines and coil, allowing heat to pass outside your home. It is a crucial part of cooling your home.
Air conditioning coil that disperses heat into the air outside your home, or alternatively pulls heated air into your home when it acts as a heating unit.
The Coefficient of Performance, which measures the heat pump’s efficiency in using electricity. You can calculate COP by dividing your system’s BTUH by the watt-hour usage of the system. Standard conditions usually call for a COP of 3.0 or more.
The Department of Federal Energy, which establishes the required efficiency for HVAC systems in the industry while monitoring its energy consumption.
The type of airflow through a furnace, it describes when a furnace takes cool air at the top of a furnace, heats it, then circulates it back to the top.
The system of pipes and vents that distribute warm or cooled air throughout your home or business.
Energy Efficiency Ratio, which is calculated by dividing the BTUH capacity of a system by the watts required to run the system.
A Broad term that describes the difference between the energy a unit produces versus the energy it consumes.
This piece contains the liquid refrigerant that cools the air inside a home, which then takes heated air and releases it outside.
Florida Power and Light, the largest provider of utility power in Florida. Sets the minimum SEER rating for HVAC units sold in Florida.
The Ground Source Heat Pump, which uses natural water sources to transfer heat out of the home.
Hard Start Kit
These are internal parts of the condenser, which makes the compressor start with maximum efficiency.
Transfers heat from burners to blowers in a furnace.
A Machine that cool and heats air by pumping it from the outside to the inside, or vice versa.
Describes the horizontal flow of air within a side-to-side oriented furnace
Heating Season Performance Factor, which measures the efficiency of a heat pump by dividing the heat it produces by the electricity it requires.
This unit is the indoor component of your heating or cooling system. It transfers heat from the indoors to the outdoors (or the reverse when used as a heater). Indoor coils are usually designed to accompany a specific outdoor unit to achieve the best efficiency levels.
Heat that is produced or reduced by a system in addition to the predicted change in temperature. It can affect the way the home feels, but it cannot be measured with a thermometer.
These are used to approximate how much heat is lost or gained by a house or structure naturally while an HVAC system is in use.
This is a name that distinguishes air conditioners that contain the condenser, compressor, and evaporator coil together internally.
Heating and cooling systems use refrigerant fluid to transfer heat from one part of the system to the other.
The copper tubes that carry the refrigerant between internal and external heating and cooling units.
Seasonal Energy Efficiency Ratio, or the total cooling of a central air conditioning unit. It is calculated by dividing the system’s average annual usage in BTU by the average annual consumption of watt-hours. FPL recommends a minimum rating of 14 or more.
HVAC systems where the compressor and condenser are located externally, but the evaporator coil is inside the structure. This is the most common form of air conditioning unit.
Sound Rating Number, which measures the noise a unit makes while operating. The ARI assign these ratings.
Copper pipe connecting the internal and external components of a split-system HVAC unit. It carries the refrigerant between the inside and the outside of the home, transferring heat between the condenser and evaporator.
Straight Cool System
Air conditioning unit that only cools, with no heating components. Alternative heating equipment might be included with it.
A form of heating that is simply a series of coils located near the air blower. It is often included with straight cooling systems.
The component that allows homeowners to measure and control the temperature of their home. Sometimes it is programmable, automatically adjusting the home’s internal temperature.
Cooling and heating capacity is sometimes measured in tons rather than BTUH. A single ton is equivalent to 12,000 BTUH.
Describes the direction of airflow through a furnace that takes air from the bottom of a system, heats it and then transfers it to the top of the system.
Water Sourced Heat Pump, which transfers heat using cooling towers, lakes, and waterways.
The process of splitting your home into sections to more effectively control the heating or cooling of your home.