Call us now ! Send us an email Murfreesboro Hwy Manchester United States

Back to Top

Call Us Today!
Call Us Today!



Here are some common terms used in the heating and air conditioning industry.
Air Diffuser: Air distribution outlet or grille designed to direct airflow into desired patterns.
Air Flow: The distribution or movement of air.
Air Handler: The portion of the central air conditioning or heat pump system that moves heated or cooled air throughout a home’s ductwork. In some systems, a furnace handles this function.
Annual Fuel Utilization Efficiency (AFUE): A rating that denotes the efficiency of gas heating equipment. It is the amount of heating your equipment delivers for every dollar spent on fuel. A higher rating indicates more efficient equipment. This rating is calculated in accordance with the Department of Energy test procedures.
Blower: An air handling device for moving air in a distribution system.
BTU (British Thermal Unit): The standard of measurement used for measuring the amount of heat required to raise the temperature of one pound of water by one degree (Fahrenheit).
Capacity: The ability of a heating or cooling system to heat or cool a given amount of space. For heating, this is usually expressed in BTUs. For cooling, it is usually given in tons.
Carbon Monoxide (CO): It is a colorless, odorless gas produced by burning any fuel. CO is poisonous, and symptoms of CO poisoning are similar to those of the flu: headaches, fatigue, shortness of breath, nausea and dizziness. The Consumer Product Safety Commission (CPSC) recommends a yearly, professional inspection.
Central Air Conditioner System: A system in which air is treated at a central location and carried to and from the rooms by one or more fans and a system of ducts.
CFM (Cubic Feet per Minute): The abbreviation for cubic feet per minute commonly used to measure the rate of air flow in an air conditioning system.
COP (Coefficient of Performance): The ratio of the rate of useful heat output delivered by the complete heat pump unit (exclusive of supplementary heating) to the corresponding rate of energy input, in consistent units and under operation conditions.
Charge: The amount of refrigerant in a system.
Compressor: The pump that moves the refrigerant from the indoor evaporator to the outdoor condenser and back to the evaporator again. The compressor is often called “the heart of the system” because it circulates the refrigerant through the loop.
Condensation: The process by which a gas is changed into a liquid at a constant temperature by heat removal.
Condenser: A device that transfers unwanted heat out of a refrigeration system to a medium (either air, water or a combination of air and water) that absorbs the heat and transfers it to a disposal point.
Cooling Capacity: A measure of the ability of a unit to remove heat from an enclosed space.
Cooling Load: Heat that flows into a space from outdoors and/or indoors.
Defrost Cycle: The process of removing ice or frost buildup from the outdoor coil during the heating season.
Duct: A pipe or closed conduit made of sheet metal, fiberglass board or other suitable material used for conducting air to and from an air handling unit.
Ductwork: Pipes or channels that carry air throughout a building.
Emergency Heat (Supplemental or Auxiliary Heat): The backup heat built into a heat pump system.
Energy Efficiency Ratio (EER): The ratio of the cooling capacity of the air conditioner in BTUs per hour to the total electrical input in watts under ARI-specified test conditions.
Filter: A device used to remove dust and other particles from the air for the purpose of reducing the load on the respiratory system and to protect the HVAC equipment. The higher the MERV rating, the better the filter.
Freon: A general term used to identify any of a group of partially or completely halogenated simple hydrocarbons containing fluorine, chlorine or bromine, which are used as refrigerants.
Heat Exchanger: A device for the transfer of heat energy from the source to the conveying medium.
Heat Pump: An air conditioner that contains a valve that allows it to alternate between heating and cooling.
Heating Seasonal Performance Factor (HSPF): The total heating output of a heat pump in BTUs during its normal usage period for heating divided by the total electrical energy input in watt-hours during the same period.
HVAC/R: Heating, ventilation and air conditioning/refrigeration.
Humidity: The amount of moisture in the air. Air conditioners remove moisture for added comfort.
Indoor Unit: This is usually located inside the house and contains the indoor coil, fan, motor and filtering device (sometimes called the air handler).
Indoor Coil: Refrigerant containing a portion of a fan coil unit similar to a car radiator, typically made of several rows of copper tubing with aluminum fins.
Infiltration: Airflow into a space, usually through walls and leaks around doors and windows.
Insulation: Any material that slows down the transfer of heat.
Matched System: A heating and cooling system comprised of products that have been certified to perform at promised comfort and efficiency when used together and used according to design and engineering specifications.
Refrigerant: A substance that produces a refrigerating effect while expanding or vaporizing.
Return Air: Air drawn into a heating unit after having been circulated from the heater’s output supply to a room.
Reversing Valve: A device in a heat pump that reverses the flow of refrigerant as the system is switched from cooling to heating.
SEER (Seasonal Energy Efficiency Ratio): A rating that denotes the efficiency of air conditioning equipment. It is the amount of cooling your equipment delivers for every dollar spent on electricity. It is the ratio of cooling delivered by a system, measured in BTUs, to the dollar cost of the electricity to run the system as measured in watt-hours. This ratio is determined using specified federal test procedures. The higher the SEER, the more efficient the unit. The more efficient the unit, the lower the operating cost.
Setpoint: The temperature to which a thermostat is set for desired comfort level.
Single Package: A year-round heating and air conditioning system that has all of the components completely encased in one unit outside the home.
Split System: A central air conditioner consisting of two or more major components. The system usually consists of a compressor, containing unit and condenser, installed outside the building and a non-compressor, containing air-handling unit, installed within the building.
Temperature: The measure of the intensity of heat that a substance possesses.
Thermostat: A temperature control device, typically found on a wall inside that consist of a series of sensors and relays that monitor and control the functions of a heating and cooling system.
Tonnage: The unit of measure used in air conditioning to describe the cooling capacity of a system. One ton of cooling is based on the amount of heat needed to melt one ton (2,000 lbs) of ice in a 24-hour period. One ton of cooling is equal to 12,000 BTU/hr.
Vacuum Pump: A pump used to remove air and moisture from a refrigeration system at a pressure below atmospheric pressure.
Ventilation: The process of supplying or removing air, by natural or mechanical means, to or from any space. Such air may or may not have been conditioned.
Zone System: A method of dividing a home into zones and enabling you to control the amount of comfort provided to each.

YP Reviews

Contact Information
Shelton's Heating and Cooling
1005 Murfreesboro Highway
Manchester, TN 37355
Phone: 931-723-4996
Fax: 931-723-3494
Hours of Operation:
Monday – Friday
7:30am – 4:00pm
Money Orders

In Business Since 1972