Gagne Heating and Air Conditioning Experts List the Most Common Words, Phrases and Acronyms You're Likely to Encounter When Talking About Residential or Commercial Heating and Cooling
Knowing the basic parts and terms associated with your HVAC system can help you determine if something is broken, if the system isn't running as efficiently as it should or if it's time for an upgrade.
If any of these situations arise, it's time to call a local AC specialist for help. If you live in Atlanta, Alpharetta or nearby, contact Gagne Heating &Air Conditioning for immediate and professional residential and commercial service.
In the meantime, here's a list of common HVAC terms to help you learn more about your heating and cooling system.
AHRI: The Air-Conditioning, Heating and Refrigeration Institute is a trade association made up of 315 member companies who manufacture residential and commercial air conditioning, commercial refrigeration equipment, heating and water heating. AHRI creates standards for rating and testing this equipment. Website: http://www.ahrinet.org/site/1/Home
Air Cleaner: A device that eliminates pollutants, allergens and other harmful particles from the air in your system.
Air Conditioner: The process of cooling, heating, cleaning, humidifying and dehumidifying air, and then distributing it throughout a space.
Air Filter: A device that traps unwanted particulates and allergens from getting into the air stream.
Air Handler: The part of your system that moves heat or air through the ductwork.
AFUE: Annualized Fuel Utilization Efficiency is a measure of how efficiently your furnace turns fuel into energy. The higher the number, the more efficient your furnace is.
British Thermal Unit (BTU): A BTU is a measurement of heat energy. One BTU is the amount of heat required to raise the temperature of 1 pound of water 1 degree Fahrenheit. BTUs can be used to measure both heating and cooling capacities.
CFM: Cubit Feet per Minute is a standard measurement of airflow. The more air being pushed through one point in a minute, the higher the number.
Compressor: The compressor is one of the most important parts of an air conditioning system. It’s a pump that compresses refrigerant, raising both the pressure and temperature.
Condensate: The moisture that collects as a result of gas cooling and reaching its liquid state.
Condenser/Condenser Coil: The condenser lets off excess heat to the outside to dissipate by turning hot, high-pressured refrigerant gas back into its cool, liquid form. (See also: Outdoor Coil.)
Cubic Feet Per Minute (CFM): This measures how many cubic feet of air passes by a particular point in the ductwork in a minute.
Damper: This piece is located in the ductwork and can be moved, opened or closed to regulate airflow. It can completely close off heat or air to a particular room or help to better regulate the air throughout the space. Dampers can be manual or automatic.
Delta T: A measurement of the difference between two temperatures or the temperature difference between two points.
Ductwork: The method by which air is transferred and dispersed throughout a home or building. It is made up of a network of hollow pipes that can be made of metal or flexible material. (Read "Fix Leaky Ducts to Improve Your Heating and Cooling System")
Energy Efficiency Ratings (EER): EERs measure the efficiency by which an appliance uses energy to run. They are calculated by dividing an appliance’s BTU output by its wattage.
Evaporator Coil: The evaporator coil turns liquid refrigerant into gas, which cools and dehumidifies the air by absorbing the heat from the air. The hot refrigerant is then carried to the condenser where the heat is let off into the outside air. (See also: Indoor Coil.)
Heat Pump: The heat pump is located outside and works like an air conditioner during the summer. In the winter, it pulls air from the outside and uses it to heat the refrigerant, which then heats your home or building. (Read "Your Heat Pump Questions, Answered")
HEPA Filter: HEPA stands for "High Efficiency Particulate Absorbing." HEPA filters trap particles in the air as they flow through the filter, creating cleaner air to blow through your home or building.
Humidifier: A machine that adds moisture to heated air during winter months as it passes from the furnace into the ductwork. (Read "Humidifiers and Dehumidifiers: Knowing What You Need")
HVAC: Stands for Heating, Ventilation, and Air Conditioning.
Indoor Coil: (see Evaporator Coil.)
Load Calculation: The analysis of a home’s heating and cooling needs to determine the energy load required by the furnace and air conditioner.
MERV Rating: MERV stands for "Minimum Efficiency Reporting Value." This rating is given to filters based on how small the holes are through which the air passes. The smaller the holes are, the higher the rating and the more efficient a filter will be.
Package Unit: A system in which the air conditioning and heating components are located in one place (always outside). (Read "Benefits of a Packaged HVAC over a Split System")
Programmable Thermostat: A thermostat that allows you to program a set schedule of temperatures (both heating and cooling) into its memory. (Read "Is a Smart Thermostat for You?")
Refrigerant: A chemical used in most air conditioning units to cool the air in the system. The most common type of refrigerant is R-22, also known as Freon. However, Freon is slowly being phased out and replaced by a more environmentally friendly refrigerant called R-410A.
Refrigerant Lines: Two copper lines that connect the unit outside to the unit inside.
Return Air: The air brought back into the system to be re-circulated after being blown out into a room.
Return Duct: The blower or mechanism that pulls the return air out of the room and back into the system to be reconditioned. Return ducts are generally located on the ceiling but can also be found on the floor in older homes.
Reversing Valve: A device located in the heat pump that reverses the refrigerant flow when the system switches from cooling to heating.
SEER: "Seasonal Energy Efficiency Ratio." This is a rating system created by the government to measure the cooling efficiency of an air conditioner or heat pump. The more efficient the system, the higher the SEER number will be.
Split System: A split system is one that has its air conditioner or heat pump components split into two separate locations. Generally, one component is outside and the other is inside. (Read "6 Advantages of Installing a Duct Free Mini-Split System")
Suction line: A line or pipe that carries refrigerant gas to the compressor from the evaporator.
Supplementary Heat: Also called "emergency heat," supplementary heat is used when the heat pump cannot compensate for below freezing temperatures outside during winter months.
Thermostat: A device (often electronic) that allows a person to adjust heating and cooling temperatures to comfortable levels. (Read "Thermostat Not Working? Here's What to Do")
Ton: A measure of cooling capacity. One ton = 12,000 BTUs/hour.
Variable Speed Motor: A mechanism that moves at different speeds to precisely control the distribution of heat and air throughout a home or building. It is usually found in high-efficiency systems.