Glossary

AFUE

Stands for Annualized Fuel Utilization Efficiency. It is a measure of your furnace’s heating efficiency. The higher the AFUE percentage, the more efficient the furnace. The minimum percentage established by the DOE for furnaces is 78%.

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.

Airflow

The distribution/movement of air.

Btu

Stands for 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.

Btuh

British thermal units per hour.

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. It is 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.

 

Condenser Coil

The outdoor portion of an air conditioner or heat pump that either releases or collects heat.

Damper

A movable plate, found 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

dB

A decibel is a unit used to measure the relative intensity of sound.

DOE

Stands for the Department of Energy. They are a federal agency responsible for setting industry efficiency standards and monitoring the consumption of energy sources.

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.

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 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, the process is reversed and head is removed from your house and released outdoors.

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.

 

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 measure equal to one millionth of a meter, or one thousandth of a millimeter.

Outdoor Coil

See Condenser Coil.

Programmable Thermostat

A thermostat with the ability to record different temperature/time settings for your heating and/or cooling equipment.

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 and the more you save. The DOE’s established minimum SEER rating for cooling is 13.00.

Split System

An HVAC system in which some components are located inside the structure of the house and some are located outside. Split systems should be matched for optimal efficiency.

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.

Two-Stage Operation

Provides two levels of heating or cooling output for greater temperature control, energy efficiency and improved indoor air quality.

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. It is 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.