This term refers to the number of times per hour a room is supplied (or removed) of air through mechanical and natural ventilation.
An appliance or system designed to extract heat and dehumidify a room or building. A room air conditioner is installed in a window or a wall and delivers conditioned air without a ductwork system. Central air conditioning uses fans and ducts to deliver cool air from a central unit to the rooms in your home.
Similar to SEER (Seasonal Energy Efficiency Ratio), AFUE measures the energy efficiency of your heating system, aka your furnace or boiler. AFUE tells you how much of your fuel is used to heat your home and how much energy is lost through exhaust. For example, a furnace with an 80% AFUE rating means that 80% of the fuel is converted into heat while 20% is lost through exhaust. AFUE and SEER ratings go down over time. If your AFUE rating is below 80%, consider replacing your unit with a more energy-efficient one.
This term refers to the process of adding coolant, or refrigerant, to an HVAC system.
This device removes heat from a liquid through a vapor-compression or absorption refrigeration cycle. The cooled liquid flows through pipes in a building and passes through coils in air handlers, fan-coil units, or other systems. This flow cools and usually dehumidifies the air. There are two types of designs: air-cooled and water-cooled.
Equipment that implements heat transfer to air when mounted inside an air handling unit or ductwork. The coil is heated or cooled by electrical means or by circulating liquid or steam inside it.
This component in the basic refrigeration cycle ejects or removes heat from the system. The condenser is the hot side of an air conditioner or heat pump. Condenser coils are heat exchangers and can transfer heat to the air or to an intermediate fluid to carry heat to a distant sink. Heat sinks include the ground (earth sink), a body of water, or air (as with cooling towers). Your central HVAC’s condenser coils are usually located in your outdoor air conditioning or heat pump unit. You should have a minimum 2-foot clearance around your outdoor unit for proper airflow.
A device that controls the operation of all (or part) of an HVAC system. It might turn a device on and off or subtly modulate the set point of components. Most controllers are automatic but have user input such as temperature set points, e.g., a thermostat.
Specialized pipes or channels for the airflow (including supply air, return air, and exhaust air) within a home.
Equipment that reduces the level of humidity from the air. It works by cooling air to the point where water turns to liquid from vapor form, which is then removed.
Also known as a condensate pan. As the refrigerant vapor is liquefied, the drain pan collects the condensate and funnels it to the drain line.
Placed over ductwork, a diffuser separates air with vanes going in different directions. It evenly distributes airflow in the desired directions.
A coil in the basic refrigeration cycle that absorbs or adds heat to the HVAC system. It can be used to absorb heat from air or a liquid. The evaporator is the cold side of an air conditioner or heat pump and is located inside your air handler or attached to the furnace.
The opening through which outside air is drawn into the building. It either replaces air in the building that has been exhausted by the ventilation system or provides fresh air for the combustion of fuel.
The facing across a duct opening, often rectangular in shape, containing multiple parallel openings through which air may be delivered to a ventilated space. The grille directs the airflow in a particular direction and prevents the passage of debris.
Part of the HVAC system that conducts heat. It allows electricity to act as fire.
A compressor that cycles both hot and cold air. It is designed to move thermal energy in the opposite direction of heat flow by absorbing heat from a cold space, which is then released to a warmer space.
This process occurs when heat moves from one area to another. It is a vital step in the process of cooling a space.
The acronym for Heating, Ventilation and Air Conditioning. Modern systems also include air cleaning and moisture control.
A measure of the air temperature outside a building.
An air-handling unit, either with a “recirculating” or “once-through” design, created for outdoor installation. They most often include their own heating and cooling devices internally.
Substance that produces a cooling effect, used in most air conditioning and cooling systems.
The seasonal energy efficiency ratio measures the energy efficiency of your air conditioning system. It is equal to the Total Cooling Output Over the Cooling Season/Total Electrical Energy Input Over the Cooling Season. It measures the total cooling of your air conditioner or heat pump in BTUs compared with the energy output in watt-hours used within the same period. The higher the SEER rating on your air conditioner, the more energy efficient it is, meaning lower energy costs to run it.
The seasonal energy efficiency ratio measures the energy efficiency of your air conditioning system. It is equal to the Total Cooling Output Over the Cooling Season/Total Electrical Energy Input Over the Cooling Season. It measures the total cooling of your air conditioner or heat pump in BTUs compared with the energy output in watt-hours used within the same period. The higher the SEER rating on your air conditioner, the more energy efficient it is, meaning lower energy costs to run it.
The condition in which the liquid refrigerant is colder than the minimum temperature required to keep it from boiling, which would change it from a liquid to a gas phase. Subcooling is the difference between its saturation temperature and the actual liquid refrigerant temperature.
A temperature-control device that monitors and regulates a heating or cooling system. It can be used to set the desired temperature and keeps the environment either heated or cooled.
A system that divides a home, office, or space into different regions to better control the temperature and effectiveness of a heating and cooling system.