The Air-Conditioning, Heating, and Refrigeration Institute (AHRI) is the trade association representing North American manufacturers of air conditioning, heating, water heating, and commercial refrigeration equipment.

The portion of your air conditioner or heating system that forces air through your home’s ductwork.

The air external to a building or device.

The temperature surrounding an object.

A valve with a small opening which permits a minimum fluid flow when the valve is closed.

In HVAC the device is an air conditioner that distributes the filtered air from the return duct over the coil/heat exchanger. This circulated air is cooled/heated and then sent through the supply duct, past dampers, and through supply diffusers to the living/working space.

British Thermal Unit. Used for both heating and cooling, BTU is a measure of the heat given off when fuel is combusted. Or for cooling, it’s a measure of heat extracted from your home.

Ability of a circuit system to store electricity. The capacitance of a capacitor is measured in farads and is determined by the formula C = q/V, where q is the charge (in coulombs) on one of the conductors and V is the potential difference (in volts) between the conductors. The capacitance depends only on the thickness, area, and composition of the capacitor’s dielectric.

Stands for Cubic Feet per Minute. A measurement of airflow that indicates how many cubic feet of air pass by a stationary point in one minute. The higher the number, the more air is being forced through the system. 1 CFM equals approximately 2 liters per second (l/s).

The process of adding refrigerant to an air conditioning system. Refrigerant is stored in a sealed system and aids in the overall cooling factor. Refrigerant moves from the indoor evaporator to the outdoor condenser and then back to the indoor evaporator.

The pump that moves refrigerant from the indoor evaporator coil to the outdoor condensing unit and back to the evaporator. The compressor functions as the heart of the system as it circulates refrigerant in a loop.

The portion of a central air conditioning system located outside the home. It functions as a heat transfer point for collecting heat from, and dispelling heat to, the outside air.

Liquid or droplets which form when a gas or cooled below its dew point.

Condenser Coil

A network of refrigerant-filled tubes where heat leaves hot refrigerant vapor. This vapor then condenses into a liquid capable of absorbing more heat.

HVAC term for controls that vary airflow through an air outlet, inlet, or duct. A damper position may be immovable, manually adjustable or part of an automated control system.

An actuator which will drive a mechanical damper variably or 2 position.

Hollow pipes used to transfer air from the Air Handler to the air vents throughout your home. Ductwork is one of the most important components of a home heating and cooling system.

Energy Efficiency Ratings (EER) measure the efficiency with which a product uses energy to function. It is calculated by dividing a product’s BTU output by its wattage.

The portion of the heat pump or central air conditioning system located in the home. It functions as the heat transfer point for warming or cooling air.

A valve that meters the levels of refrigerant through a temperature or pressure control

A registered trademark for a chlorofluorocarbon (CFC) gas that is highly stable and that has been historically used as a refrigerant.

The heat pump is an air conditioner that reverses the process of removing heat from the inside of the house in summer to absorbing the heat from outside air and moving it inside in winter. It is effective down to temperatures around 30 degrees Fahrenheit. At that point either a gas furnace or an air handler with supplemental electric heat will be needed to help heat your home.

The measurement of electrical energy per second. Standard frequency is 6- Hertz.

A humidistat (sometimes called a humidistat control) is a device that works with a home’s heating and cooling system to automatically adjust the amount of moisture in the air to maintain a specific humidity level throughout the home.

A measure of the moisture content of air; may be expressed as absolute, mixing ratio, saturation deficit, relative, or specific.

HVAC Stands for (H)eating, (V)entilation, and (A)ir (C)onditioning.

The Minimum Efficiency Reporting Value is the standard comparison of the efficiency of an air filter. The MERV scale ranges from 1 (least efficient) to 16 (most efficient), and measures a filter’s ability to remove particles from 3 to 10 microns in size.

Like central split systems, mini splits have two main components: an outdoor compressor/condenser, and an indoor air-handling unit. A conduit, which houses the power cable, refrigerant tubing, suction tubing, and a condensate drain, links the outdoor and indoor units.  It is a ductless system which supplies air through an indoor unit.

In some parts of the country, a packaged system is the perfect solution. The heating, cooling and air handling functions are self-contained in one unit. Usually installed at ground level on the roof or outside a mobile home. This unit is only installed outside. These systems can be heat pumps, electric heat strips or a gas heater as the primary heat source.

Most commonly used motor. A capacitor is usually used to help run the motor and generate more torque. These motors can run either single or multiple speeds.

The central heating or cooling system contains a fan that gets its air supply through these ducts, which ideally should be installed in every room of the house. The air from a room will move towards the lower pressure of the return duct.

SEER stands for Seasonal Energy Efficient Ratio. Air conditioners are rated according to their SEER. The higher the SEER rating of your air conditioner, the higher the efficiency, the more you save on electricity. The U.S. DOE (Department of Energy) revised its energy conservation rules in 2006 requiring all new products to have a 13.0 SEER rating or higher. Manufacturers of air conditioners can offer SEER ratings of 13.0 to 21 or higher. Find out more at energy.gov

Refers to an air conditioner or heat pump that has components in two locations. Usually, one part of the system is located inside (evaporator coil) and the other is located outside your home (condenser coil).

Auxiliary or emergency heat, usually electrical resistance heat, provided when temperatures are below a heat pump’s balance point.

A device that creates a constant evaporator temperature by regulation of refrigerant flow through the system

A ton is the cooling capacity of an air conditioning system. It’s equal to the amount of heat required to melt one ton of ice over 24 hours. For instance, a one-ton air conditioner would be rated at 12,000 BTU per hour (BTUh).

The ultimate solution to providing you with consistent, customized home comfort, despite the ever-changing weather.

If you purchase a variable speed air handler or a variable speed gas furnace with your unit; you will enhance both the comfort and the efficiency of your air conditioning or heat pump system. They operate so efficiently that they can actually increase the efficiency rating of your central air conditioning system and offer you added energy savings in any season.

Ideal for high-efficiency air conditioners, a variable-speed motor functions much like a two speed, only with several speeds of operation. When compared with single- or two-speed motors, it facilitates smoother cycling and more precise performance control, as well as the most quiet operation, highest energy efficiency and least stress on mechanical parts.