The 8 Important Parts and Functions of an HVAC System

December 14, 2021Back to blog
York Mills HVAC cleaning service

HVAC System

HVAC stands for heating, ventilation, and air conditioning. This system is installed in residential houses and commercial buildings to provide heating during cold seasons and cooling in hot weather. HVAC systems are specifically made to provide comfort and high indoor air quality. Ventilation, on the other hand, is the process of exchanging or replacing air within a space. It removes odor, heat, smoke, moisture, airborne bacteria, carbon dioxide, and other harmful particles.

The HVAC System At Work

We now know the three main functions of an HVAC system, but how does it really work? These three main functions are interrelated, especially when providing acceptable indoor air quality and thermal comfort. There are nine parts of an HVAC system that you should know about.

1.Condensing Unit

This unit is usually placed outside the house because condensing units contain refrigerant gas-cooled by exchanging heat with the outside air. The condensed gas will turn into liquid form and be delivered to the evaporator coil where it is used to cool the air inside the house.

2.Air Ducts

Air ducts or ductwork is a part of an HVAC system responsible for air distribution. They are typically placed on the insides of walls and ceilings. The air passes through these ducts into the house. The reason why they should be cleaned from time to time.

3.Heat Exchanger

Located inside the furnace, this part of the HVAC system is activated by the thermostat. It functions when hot or warm air is needed by quickly warming or heating up the air from outside to the furnace. The heated or warm air then passes through air ducts supplying it inside the house.

4.Refrigerant Lines

Metal tubes (usually aluminum or copper) that carry liquid to the evaporating coil and back to the condensing unit. Its function is part of the cooling process.


A thermostat is the control center for your home’s central cooling and heating system. It functions based on your temperature setting. It compares your set temperature with the ambient temperature in your home. That is why the thermostat should be placed on a spot where it can’t be influenced by something near like the registers or in the kitchen.


The furnace is responsible for creating the heat that drives the hot or warm air into your home or building. Because of its size, furnaces are usually placed in the attic or basement. The furnace burns fuel such as natural gas or heating oil to generate heat.

7.Evaporator Coil

The evaporator is located on the cold side of the air conditioner. Its main function is to receive liquid refrigerant and turn it into gas, which then cools and dehumidifies the air. In this process, the working fluid or refrigerant takes away the heat from the air and cools it off.


The main function of a compressor is to mechanically compress the refrigerant, greatly raising its pressure and its temperature. It converts refrigerant from gas to liquid and sends it to the coils. This part of the HVAC system is located on the hot side of the air conditioner with the condenser.

The processes that make HVAC systems work are complex. The key to keeping the system running is regular maintenance. If you are having problems with your HVAC system, you may contact us, Sem’s Duct Cleaning Services, and we will be more than willing to help.

Trustful Air Duct Cleaning Provider

Over more than 25 years of experience in the field of air duct cleaning, Sem’s experts have perfected their knowledge in order to provide high-quality service to each and every individual. We specialize in:

The buildings we serve vary from industrial spaces in Toronto and commercial spaces in Vaughan to business offices, gyms, hospitals, and universities.

When hiring Sem’s Duct Cleaning, you can be sure to receive the same quality of service on your first, second or tenth visit. Our reputation speaks for itself. Count on our professionals and, in turn, you will get a cleaner and healthier home whether you live in Richmond Hill or North York

Let Sem’s Duct Cleaning help improve your indoor air quality and allow your loved ones to enjoy the surrounding beauty and the breath of each coming season!

Check more information on “Tips to Lower Heating Cost in the Winter” and aboutChoosing the Right Air Duct Cleaning Provider

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