HVAC Terms to Know

Air Handler: The indoor component that moves the heated or cooled air throughout the duct work in your home. This is usually a fan coil or a furnace.

BTU-British Thermal Unit: the amount of energy needed to change the temperature of one pound of water, by one degree Fahrenheit. In your home, this represents the measure of heat given off when fuel is burned for heating or the measure of heat extracted from your home for cooling. We use this measurement to determine the exact capacity of heating or cooling your home requires.

Capacity: the output or producing ability of a piece of equipment. Heating and cooling load capacities are measured in BTUs per hour.

Carbon Monoxide-CO: a poisonous, odorless, flammable gas produced when carbon burns with insufficient oxygen. Poor combustion is just one cause of CO.

CFM- Cubic Feet per Minute: a standard measure of air flow volume. A conventional system requires 400 CFM per ton (12,000 BTU) of air conditioning.

Compressor: is the heart of the outdoor unit and is the central point of a heat pump or air conditioning system. The compressor pumps, or compresses, the refrigerant gas into the condenser coil, then liquid metered into the evaporator coil to be recirculated.

Condensing Unit: the outdoor unit, component of an air conditioning system

Condenser Coil: is the outdoor coil on a central air conditioning system; on heat pump in cooling is the outside but during heat the inside coil becomes condenser the sole purpose is to change the state of the refrigerant from a gas to a liquid

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DB- Decibel Level: sound level or noise level

Damper: moveable plate(s) that open or close to control air volume, often used to balance airflow and can be used in zoning systems to regulate airflow to different rooms automatically

DOE- Department of Energy: is a federal agency responsible for establishing industry efficiency standards and monitoring the consumption of energy sources

Ductwork: pipes, cavities or rectangular channels that carry forced air throughout a home, structure, office, store, etc. The performance of your HVAC system is dependent upon these ducts to carry treated air to where it is needed

EAC- Electronic Air Cleaner: equipment that filters air down to microscopic size. Some pollens, bacteria and viruses can be filtered and destroyed with some systems

Energy Star: a label used to identify HVAC equipment that meet, or exceed, the EPA guidelines for energy

EPA- Environmental Protection Agency: develops and enforces federal environmental regulations

Gas furnace heat exchanger: transfers heat from inside burner to air stream and circulated by blower

Heat Pump: is an HVAC unit that cools or heats by transferring or moving heat from one space to another; in winter it draws heat from outdoor air and circulates; in summer it reverses the process and removes heat and releases it outdoors

HSPF- Heating Seasonal Proficiency Factor: is a rating to measure the heat efficiency of a heat pump. The higher the number the more efficient the unit.

Humidifier: an indoor air quality product that deposits moisture to heated air as it passes from the furnace into the ductwork to distribute throughout the home

Humidistat: an automatic control device used to maintain the humidity at an adjustable value of relative humidity

HVAC: heating ventilating air condtioning.

Indoor Coil: will get cold as the blower from furnace or air handler passes warm air across it during summer; for heat pump this operates the same in a/c but exchanges warm air in winter as the coil is a condenser during winter

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MERV Rating- Minimum Efficiency Reporting Value: is used to rate an air filter, describing the size of the holes in the filter that allows air to pass through. The higher the MERV rating the smaller the holes are in the filter and the higher the efficiency

Micron: a unit of measure equal to one millionth of a meter or one thousandth of a millimeter

Odors/Chemicals– air contaminants in the form of gas

Package Unit: a heating and/or cooling unit that comes together in one self-contained package

Particles: any substances measuring less than 100 microns in diameter

Programmable Thermostat: a thermostat that has the ability to record different temperatures and time settings for controlling a heating and/or cooling system

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Refrigerant: has many trade names such as freon, puron etc. is the fluid and/or gas that evaporates and condenses throughout a system absorbing heat in the evaporator coil and releasing into the condenser. Refrigerant should not be needed unless a leak is in the equipment.

Refrigerant Lines- Line Set: two (2) copper lines that connect the outdoor unit to the indoor unit

Scroll Compressor: compressor that operates in a circular motion as opposed to the up and down piston action

SEER- Seasonal Energy Efficiency Rating: refers to the efficiency of an air conditioner or a heat pump. The higher the SEER the more superior the energy performance

Split System: a combination air conditioner or heat pump with both indoor and outdoor components

Thermidistat: monitors both humidity and temperature and controls heating, cooling and humidity to preferred levels

Thermostat: a control device consisting of sensors and relays that monitor and activate the functions of cooling, heating and air devices in order to regulate temperature for a specific space

Ton: unit of measurement for sizing cooling capacity, one ton is equivalent to 12,000 BTU

Two Stage Operation: means a/c or heat pump has a compressor with 2 levels of operation

Up Flow: a type of furnace or air handler that draws cool air from the equipment bottom and discharges warm or conditioned air from the equipment top into, or out of air ducts

Variable Speed Drive: continuously calculates and adjusts the frequency and voltage providing only the power the motor needs

Ventilator: a system that exchanges stale, recirculated indoor air with fresh, filtered outside air

Zoning: a method of dividing a space into independently controlled comfort areas for enhanced comfort and efficiency

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Call us at 740-667-6784 or toll-free at 800-927-6781 to learn more about our heating and cooling solutions.