Terms and technical definitions for heating and air conditioning...
Airflow
The distribution or movement of air.
Air Handler/Coil Blower
The indoor part of an air conditioner or heat pump that moves cooled or heated air throughout the ductwork of your home. An air handler is usually a furnace or a blower coil.
BTU
A British thermal unit is a unit of heat energy. One Btu is the amount of heat required to raise one pound of water by one degree Fahrenheit. The higher the Btu rating, the greater the heating capacity of the system.
Carbon Monoxide
An odorless, colorless, tasteless, poisonous and flammable gas that is produced when carbon burns with insufficient air.
Central Air Conditioning System
System in which air is treated at a central location and distributed to and from rooms by one or more fans and a series of ducts.
CFM
Stands for Cubic Feet per Minute. This measurement indicates how many cubic feet of air pass by a stationary point in one minute. The higher the number, the more air is being moved through the ductwork by the system.
Compressor
The part of the outdoor air conditioner or heat pump that compresses and pumps refrigerant to meet household cooling requirements.
Communication Module
A component of a SunSource® Home Energy System, a communication module allows you to view system status and environmental benefits in real time.
Condenser Coil
The outdoor portion of an air conditioner or heat pump that either releases or collects heat, depending on the time of the year.
Damper
A movable plate, located in the ductwork, that regulates airflow. Dampers are used to direct air to the areas that need it most. Typically used in a zoning application.
Dry-charged unit
An air-conditioner or heat pump that is shipped dry and charged with refrigerant at the place of installation. Dry-charged units are appropriate for homeowners who need a replacement unit compatible with R-22 refrigerant.
Dual Fuel
A comfort system that pairs an electric heat pump with a gas furnace, providing an energy-efficient alternative to the conventional furnace/air conditioner combination.
Ductwork
The method by which air is channeled from the furnace or the blower coil throughout your home.
ENERGY STAR®
An EPA (Environmental Protection Agency) designation attached to HVAC products that meet or exceed EPA guidelines for high-efficiency performance above the standard government minimums.
EPA
The Environmental Protection Agency develops and enforces federal environmental regulations. The EPA oversees the nationwide ENERGY STAR® program.
Evaporator Coil
The part of the air conditioner or heat pump that is located inside the air handler or attached to the furnace. Its primary function is to absorb the heat from the air in your house.
Heat Exchanger
Located in the furnace, the heat exchanger transfers heat to the surrounding air, which is then pumped throughout the home.
Heat Pump
A heat pump is an HVAC unit that heats or cools by moving heat. During the winter, a heat pump draws heat from outdoor air and circulates it through your home's air ducts. In the summer, it reverses the process and removes heat from your house and releases it outdoors.
Horizontal Flow
When an air handler or furnace is positioned on its side and circulates air in one end and out the other. Ideal for attic or crawl space installations.
Humidifier
An indoor air quality device that introduces moisture to heated air as it passes from the furnace into the ductwork for distribution throughout the home.
Humidistat
An automatic device used to maintain humidity at a fixed or adjustable set point.
HVAC
Heating, Ventilation and Air Conditioning.
Indoor Coil
See Evaporator Coil.
MERV Rating
The MERV (Minimum Efficiency Reporting Value) rating of a filter describes the size of the holes in the filter that allow air to pass through. The higher the MERV rating, the smaller the holes in the filter, the higher the efficiency.
Micron
A unit of measure equal to one millionth of a meter, or one thousandth of a millimeter.
Outdoor Coil
See Condenser Coil.
Particles
Any substances measuring less than 100 microns in diameter. The EPA has found that small particles (less than 2.5 microns) are responsible for the health effects of greatest concern.
Programmable Thermostat
A thermostat with the ability to record different temperature/time settings for your heating and/or cooling equipment.
R-22 Refrigerant
The old standard for residential air conditioners, R-22 refrigerant is now being phased out by the U.S. EPA. Lennox offers dry-charged units for those who still have R-22 compatible systems.
R-410A Refrigerant
A chlorine-free refrigerant that meets the EPA's newest, most stringent environmental guidelines.
Refrigerant
A chemical that produces a cooling effect while expanding or vaporizing. Most residential air conditioning units contain the standard R-22 refrigerant, or Freon.
Refrigerant Lines
Two copper lines that connect the outdoor air conditioner or heat pump to the indoor evaporator coil.
Scroll Compressor
A specially designed compressor that works in a circular motion, as opposed to up-and-down piston action.
SEER
The Seasonal Energy Efficiency Ratio is an energy efficiency rating for air conditioners. The higher the SEER, the better the energy performance, the more you save. The DOE's established minimum SEER rating for cooling is 13.00.
Thermostat
Usually found on an inside wall, this device operates as a control to regulate your heating and cooling equipment, allowing you to adjust your home comfort at the touch of a switch.
Ton
Unit of measurement for determining cooling capacity. One ton equals 12,000 Btuh.
Upflow
When an air handler or furnace is installed in an upright position and circulates air through the side or bottom and out through the top. Typically used in basement, closet and attic installations.
Variable Speed Motor
A motor that automatically adjusts the flow of warm or cool air for ultimate comfort.
Ventilator
A system that exchanges stale, recirculated indoor air with fresh, filtered outside air.
Zoning
A method of partitioning a home into independently controlled comfort zones for enhanced comfort and efficiency.