HVAC Glossary
Though your definitions of comfort may be different than your neighbors, knowing these terms can help make your search for improved comfort and efficiency much less confusing and much more effective.
AFUE – Annual Fuel Utilization Efficiency
Indicated as a percentage, your furnaces AFUE tells you how much energy is being converted to heat. For example, an AFUE of 90 means that 90% of the fuel is being used to warm your home, while the other 10% escapes as exhaust with the combustion gases. BTU British Thermal Unit. Used for both heating and cooling, BTU is a measure of the heat given off when fuel is combusted. Or for cooling, its a measure of heat extracted from your home. One BTU is equal to the heat given off by a wooden kitchen match.
BTU – British Thermal Unit
Used for both heating and cooling, BTU is a measure of the heat given off when fuel is combusted. Or for cooling, its a measure of heat extracted from your home. One BTU is equal to the heat given off by a wooden kitchen match.
Capacity
The ability of a heating or cooling system to heat or cool a given amount of space. For heating, this usually expressed in BTUs. For cooling, it is usually given in tons.
Condenser Coil
Part of the outdoor portion of a split-system airconditioner or heat pump. By converting refrigerant that is in a gas form back to a liquid, the coil sends heat carried by the refrigerant to the outside.
Damper
A type of valve used in duct work that opens or closes to control airflow. Used in zoning to control the amount of warm or cool air entering certain areas of your home.
Downflow
A type of furnace that takes cool air from the top and blows warm air to the bottom—common where your furnace must be located in a second-floor closet or utility area.
EAC – Electronic Air Cleaner
An electronic device that filters out large particles and contaminants in indoor air. It then electronically pulls out tiny particles that have been magnetized, such as viruses and bacteria, drawing them to a collector plate.
Fan Coil
An indoor component of a heat pump system, used in place of a furnace, to provide additional heating on cold days when the heat pump does not provide adequate heating.
Geothermal Heating
Geothermal heating is a method of heting and cooling a building. It takes advantage of the natural stable warmth stored in the earth. Normally the earth is around 55°F (12.8°C). This is accomplished by one of a number of methods. A heat pump uses the extracted water or transfer fluid as a heat source in winter and a heat sink in summer. Some systems use part of the heat to heat the building’s hot water.
Heat Pump
A heat pump extracts heat from a liquid that is at a higher temperature than its surroundings; can be used to transfer heat from a reservoir outside in order to heat a building.
HVAC
Term used for Heating, Ventilation and Air Conditioning.
Horizontal Flow
A type of furnace, installed on its side, that draws in air from one side, heats it and sends the warm air out the other side. Most often used for installations in attics or crawl spaces.
Humidifier
A piece of equipment that adds water vapor to heated air as it moves out of the furnace. This adds necessary moisture to protect your furnishings and reduce static electricity.
Payback Analysis
Overall measure of the efficiency and value of your home comfort system. By combining your purchase price and ongoing operating costs, a payback analysis determines the number of years required before monthly energy savings offset the purchase.
SEER – Seasonal Energy Efficiency Rating
Is a measure of the cooling efficiency of your air conditioner or heat pump. The higher the SEER number, the more efficient the system is at converting electricity into cooling power.
