HVAC Terminology For Beginners

Understanding HVAC terminology will help you communicate better with your HVAC technician. It will also help you understand more about your system and its parts.

HVAC systems can be costly and when spending your hard-earned money it can add value to your decisions to have communication that is effective so you and the technician can understand your needs, wants, and problems.

If you are sourcing quotes for a new commercial HVAC system or commercial repair millions of dollars may be at stake.

In this article, we will cover all the terminology to help you not just understand the wording but also understand how you can communicate effectively with the technician.

There are many terms and acronyms associated with HVAC systems and installation in this extensive glossary below you will have all the words and terminology explained in a way you can understand.


Heating, Ventilation, & Air Conditioning Commonly Used Terms


HSPF – Heating Season Performance Factor: this means the rating determining the efficiency of the heat pump.


SEER – Seasonal Energy Efficiency Ratio: This means the rating of the efficiency of the cooling system.


ACH – Air Charges Per Hour: this means the number of times per hour the space receives 100% new air.


VAV – variable air volume: this refers to the HVAC system adjusting itself to meet the required temperature.


The Thermostat – is a device that controls the air temperature that you control manually by hand within the building.


Subcooling – this refers to the condition in which the liquid refrigerant is cooler than the minimum temperature.

Split System 

Split System – this is a type of HVAC unit that allows you to control the temperature in different areas of the premises. For example, you can have the lounge room temperature set to a different temperature than your bedroom.


Refrigerant – refrigerant is a chemical used in the HVAC system that helps cool the air.

Heat Transfer 

Heat Transfer – this refers to when heat is transferred from one area to another. 


Chiller – this device removes heat from a liquid through vapor absorption or compression in the refrigeration process.


Coil – equipment that enables heat transfer to air.


Controller – the device that controls the operation of the HVAC unit enabling you to set the temperature, air speed, humidity levels, etc.


Ductwork – is the pipes or channels that allow the air to flow to the directed area of the air outlets.


HVAC is short for heating, ventilation, and air conditioning.


An evaporator is a common component in the refrigeration cycle that absorbs or adds heat.


A furnace is a part of the HVAC unit that adds heat to the air immediately by burning natural gas or oil.


Now you have some of the most used terminologies in the HVAC industry you will have the ability to communicate better with your HVAC company and technician. This article is a great reference for more basic HVAC Terminology terms.