HVAC 101: What Is HVAC System and How Does It Work?

HVAC 101: What Is HVAC System and How Does It Work?

Did you know that consumers in the USA spend $14 billion a year on HVAC service? Despite that, many homeowners are unsure of what it does. If you’ve caught yourself wondering what is HVAC system, then this guide is for you.

If you are not sure what HVAC even means, much less what it does, you are not alone. Let’s start with the basics: H is for Heating, V is for Ventilation, and AC is for Air Conditioning.

Simply put, an HVAC system has these three parts to help move air between indoor and outdoor areas. It regulates the temperature, too, by heating and cooling your home. A good HVAC system will help maintain comfortable levels of humidity and air quality in order to create healthy and safe conditions indoors.

Important Parts of HVAC System

There are many different parts included in the HVAC system. Need a breakdown of what all of them do? Here’s a quick guide with definitions to help you better understand your HVAC system.

Air Handling Unit

The air handler can be located in the attic, basement, or even a dedicated closet. It both delivers and draws air through the system, and helps keep it regulated. Some of the key parts of an air handler are the coil, blower motor, and air filter.

Blower Motor

Once the air hits a preset temperature, the blower motor moves it along. Then it travels through your home through the air ducts. There are two types of motors: single-speed motors and variable-speed motors.

Air Filter

Before the air can circulate through the system, it passes through a filter. This helps remove some of the allergens, dust, dirt, smoke, and other pollutants found in the air.

But not all air filters are the same, since they have different levels of filtration. Luckily, you can check the MERV rating before selecting one that is best suited for your filtration needs. They are different kinds, too, like fiberglass filters, and pleated carbon filters.

Air Ducts

Once the air has been filtered through the air handling unit, it is allowed to enter the air ducts. Air ducts are the passages that help deliver and remove air. Because these play such an important role in your HVAC system, it’s important to have them checked and cleaned regularly.


Furnaces are a very common way to heat the home. This is done by heating air or boiling water, and then distributing it by way of baseboard heaters, radiant floor systems, steam radiators, or ducts. Boilers and furnaces can be forced air, hot water, or steam systems.

Heat Pump

Heat pumps work well in milder climates since they move air rather than generate heat. They are an energy-efficient solution to boilers and furnaces. Some types are geothermal, air-to-air, gas-fired heat pump, and water source.


The thermostat is probably the most easily recognizable part of the HVAC system. Located on the wall, it helps control the temperature in your home. It does this via temperature sensors.

There are different types of thermostats, like non-programmable, programmable, Wi-Fi, and Smart. Non-programmable ones are adjusted by hand, while programmable ones can be pre-programmed to change the temperature even when you are not at home. Wi-Fi and Smart systems can be accessed remotely through Wi-Fi from any device that has an internet connection.


Have you noticed that a portion of your HVAC system is outside? That very important part is a condenser. Hint: if you want details, check out https://www.schneidermechanical.com/what-does-your-hvac-systems-condenser-unit-actually-do/  for more useful information.

HVAC System Types

There are a few kinds of HVAC system types out there. Most people are familiar with the Central AC System, but there are also Split and Window AC, and Packaged Heating and Air Conditioning Systems.

How Long Do HVAC Systems Last?

One of the biggest concerns about HVAC systems is that they’ll give out unexpectedly. Usually, this is because of age and lack of proper maintenance. Most last around 15 to 25 years if they are well taken care of.


If your system is malfunctioning, start by checking the power first. Sometimes a tripped circuit-breaker is the culprit. Move on to the thermostat, and make sure that it has power or batteries, depending upon what it relies on.

If you were utilizing heating, then take a look at the furnace to see if it is functioning, and see if you can reset it first. If you were using your AC, check if there is air coming out. If not, look for water below the unit and see if that has affected the coils.

For ventilation issues, start by taking a look at the filter. Depending on the filter size they may need to be changed every month, two months, or even six to twelve months.

What is HVAC System Routine Care?

Rather than waiting for problems to occur, it’s a good idea to develop a maintenance routine for your HVAC system. Everything from clogged filters to dead batteries in your thermostat can cause issues.

Start by regularly checking supply and return vents for any obstructions. If you have an outdoor unit, likewise check that for debris. It’s also important to set reminders to change the air filters so that they can function correctly.

Ready to Learn More About HVAC?

Since heating and cooling your home is one of the biggest expenses, it’s important to understand what is HVAC system. And don’t forget to schedule a check-up for it every year with a professional!