HOW DOES A HVAC SYSTEM WORK?

What Does HVAC Stand For?

The term “HVAC” stands for heating, ventilation, and air conditioning—an umbrella category to describe the heating and air conditioning systems in your house. It also encompasses the role mechanical or natural ventilation plays in keeping your house at the ideal temperature and humidity.

Though these systems are collectively called HVAC for short, you might also hear them called an HVAC system or HVAC unit. All of these names are really blanket terms for the combination of three systems—heating, cooling, and ventilation—that work to keep your house at a comfortable temperature and control the indoor air quality.

Not only are HVAC systems used in your home, but they’re also everywhere you look, from residential or commercial buildings to airplanes and even cruise ships.

How Does an HVAC System Work?

At a basic level,HVAC system works

by drawing in cool air through the ventilation system, heating the air, and then redistributing it throughout your home—or vice versa with cool air. No matter what type of HVAC system you have, the components have the same functions. However, HVAC systems can work in several different ways depending on the type of system you have.

Air Conditioning Systems

Air conditioning systems transfer heat and humidity from inside a home to outside, cooling the indoor environment. AC units use refrigerant, which is compressed to increase the refrigerant's pressure and temperature before it flows to a condenser. Once it reaches the condenser, the heat from the refrigerant is released outside of the home and the refrigerant itself is condensed back into a liquid.

Finally, the refrigerant goes through a pressure-lowering valve, which cools it, allowing it to evaporate and once again absorb indoor heat. At this point, the cold refrigerant returns to the compressor and the process repeats itself to continue cooling the home.

Heat Pumps

Heat pumps work similarly to air conditioners, but they can heat a home as well as cool it. Like air conditioners, heat pumps use compressed and condensed refrigerant to absorb heat from one area and transfer it to another.

During the cool months, the heat pump can trap heat from outside and transfer it inside the home—even when it's cold outside, there's enough heat energy for the refrigerant to grab a

nd transfer inside. In the warmer months, the process can be reversed, with the refrigerant transferring indoor heat outside to cool the home.

Furnaces

Unlike heat pumps and air conditioners, furnaces can't cool a home; they're only used for heating. They traditionally use a fuel source, like oil or propane, to create heat and distribute it throughout the home using the home's vents and ductwork.

However, there are also electric furnaces, which use an electrical current to warm up the indoor air. Electric furnaces are usually more energy efficient and less expensive to install than gas furnaces, but they're not quite as effective as gas furnaces at heating homes during really cold outside temperatures.

In combination, these systems keep your home comfy all year round. Your thermostat acts as the command center for your HVAC unit, giving you the ability to adjust the temperature as needed.

There are a large number of electrical components needed to keep these systems

running.