AIR HANDLER– The portion of an air conditioner or heating system that forces air through your home's duct work.

BLOWER MOTOR – Located typically in a furnace/air handler, this motor is responsible to move air over the coil to either heat or cool it.

BURNOUT – When the compressor motor heats up so much that it burns itself out, burning the refrigerant in the process and creating an acid sludge in the form of thick black residue that is extremely difficult to flush from lines.

CAPACITOR – A device that stores an electric charge and helps give a boost of power to motors and compressors.

CAPACITY – The ability of a cooling or heating system to heat or cool a given amount of space. Cooling is usually expressed in tons and heating in BTUs.

COMPRESSOR – Part of a split system heat pump or A/C's outdoor portion that circulates the refrigerant through the system. The refrigerant is responsible for taking in heat or removing it to control temperature within a home.

CONDENSER COIL – Part of a split system heat pump or A/C's outdoor portion that converts refrigerant in gas form back to liquid, thereby transferring heat contained in the refrigerant to the outside of your home.

DUCT WORK – Hollow piping that runs throughout your home and transfers air from the air handler to your home's air vents.

EVAPORATOR COIL – The part of a split system heat pump or A/C unit that is located indoors, most often in the attic. The evaporator coil functions to cool and dehumidify your home's air by converting liquid refrigerant that passes through into a gas (or vice versa) depending on whether it is in heating or cooling mode.

HVAC – Acronym for Heating, Ventilation and Air Conditioning.

M099 – A refrigerant that is the closest match to R-22 of all “no oil change” replacement refrigerants. M099 has a significantly lower discharge temperature which may prolong
compressor life.

PACKAGE UNIT – A single unit (as opposed to a split system) that consists of the evaporator, condensing coils, heaters, compressor, fan and blower motor all in one casing.

PLENUM – A specific section of the duct work (an air distribution box) where air is distributed in different directions.

R-22 – A refrigerant circulated through a unit that has long been used in a variety of air conditioning and refrigeration applications. New R-22 can no longer be used in new systems effective 2010, but can be produced until 2020 in service quantities.

SEER – the Seasonal Energy Efficiency Ratio. A measure of the cooling efficiency of your A/C unit or heat pump. The higher the number, the more efficiently the system converts electricity to cooling power.

SPLIT SYSTEM – A system that has components in two locations, usually one outside (condenser) and one inside (air handler/furnace).

THERMOSTAT – Component of a system that is used to control your A/C or heat pump.

THERMOSTATIC EXPANSION VALVE – Commonly called a TXV valve. This important valve meters the flow of liquid refrigerant entering the evaporator at a rate that matches the amount of refrigerant being converted to gas in the evaporator.