How does your HVAC system work?

young woman wearing red shirt in kitchen adjusting thermostat

As homeowners, we expect each system in our house to work automatically and as intended each time we go to use it. However, this isn’t always the case, often requiring the assistance of a professional. Nevertheless, it helps to know how systems such as your HVAC system work so that you have a better understanding of what steps your technician is taking to fix it. 

Let’s start with the basics: your thermostat
Just like lifting the handle on your kitchen faucet causes water to come out, using your thermostat is the first step in how your HVAC system works. The thermostat tells the system whether to engage the furnace or the air conditioner unit and to what temperature you want your home to be. Think of it as the brains of your HVAC system.

Now, let’s move on to your furnace and AC unit
As already mentioned, there are two main units: your furnace and your AC unit. Your furnace is usually a rectangular hub in your basement or a storage closet. It contains lots of electrical components, metal “tunnels” that run into it, and contains your blower unit (more on that later).

Your AC unit is most often an outside, square-shaped fixture. Sometimes, your AC unit and furnace can be an all-in-one called a “package unit”, though these are less common today than they were in the 90s.

That has to flow somewhere: your ductwork
Your furnace and AC, as a part of your HVAC system, work by sending cooled or heated air throughout your house via ductwork. That’s the metal “tunnels” we referenced above. Many of us are familiar with the famous scene from Die Hard with Bruce Willis climbing through the much larger ductwork in a commercial building. Nevertheless, the principle is the same: ductwork transports air throughout your home.

But wait, what makes the air warm or cold?
That’s controlled by the pilot light within the ignition chamber (for warm air) and the compressor and evaporator coils (for cold air). Depending on the temperature you’ve set your thermostat to, these components will heat or cool the air moving through your home to the desired temperature.

So how does it flow through your ductwork?
That’s the result of your blower within your furnace. It’s worth noting that your blower works in conjunction to send cooled air from your AC unit throughout your ductwork. While contained within the furnace, your blower plays its role depending on the season.

Don’t overlook the importance of a return air vent
Finally, your ductwork should include a special type of component: a return air vent. This pulls warm air from the various parts of your home, recycling it and cooling it as a part of the AC process.

Does your HVAC system work as intended?
If not, let us know. If turning on your thermostat doesn’t start the system, if air doesn’t blow out at the expected temperature, or if you need to install a return air vent, we can help. Contact us at (801) 980-0903 to schedule your appointment, or get a free quote online via our easy-to-use web form here.

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