By almost any measure, the average American’s energy bill is dominated by heating and cooling costs. Here in the Midwest, where a 60-degree day can give way to six inches of snow in the blink of an eye, that probably doesn’t come as a surprise.

But despite this, for many people the HVAC system is still kind of a mysterious thing. So we thought it would be interesting to take a few minutes and break it all down: what it is, how it works, and how to use it more efficiently.

The Really Super Basics: Where is it?

This might sound simple at first, but take a moment to think it over. In addition to your central furnace—usually located somewhere out of the way like a basement or attic—there’s also the outdoor air conditioning unit, which dumps heat outdoors while circulating cooler air back into your home.

There’s also the thermostat, which allows you to control the temperature, switch the system on and off, or program when you want your HVAC to operate. And finally there’s the ductwork: Traveling through your floor, walls, and ceiling, the system of vents and returns touches every room in your home to keep air circulating. (Pro tip: If you’re concerned about the efficiency of your system, make sure your ducts are properly sealed. Leaky ducts could result in a system that has to work harder to control your home’s temperature.)

So where is your HVAC system? Maybe a better question is, where isn’t it?

The Not-So-Basic Basics: How does it heat and cool my home?

Although your furnace and air conditioner both help keep your home a comfortable temperature throughout the year, they are largely independent systems. Here’s how they work:

• Heating: To keep your home warm, a gas furnace uses energy to heat air via the ‘heat exchanger.’ The heat exchanger is a set of tubes that heated air moves through. Your furnace’s blower then pushes air through the ductwork and across the heat exchanger. In doing so, the air safely scrubs the heat from the heat exchanger while leaving unwanted gases in the tubes of the heat exchanger to be exhausted outside.If your home uses a gas furnace, it’s likely a forced-air system that uses a natural gas burner to heat air. As cool air is drawn into the system, it’s warmed by the gas burner before being circulated through the rest of your house. Some kinds of gas furnaces even utilize steam to heat a home, although these systems tend to be less common.
• Cooling: Your air conditioner uses a combination of electricity and refrigerant to lower the temperature of the air that passes around it. Interestingly, one of the byproducts of this process is heat—which is why your A/C unit sits outdoors.

Graphic courtesy of Service Champions.

The Let’s-Save-Some-Money Basics: How can my system use less power?

If you’re in the market for a new HVAC system, the first thing to do is see how it rates with ENERGY STAR®. Investing in a more efficient system up front leads to long-term energy savings over the life of the equipment.

If you’re not shopping around for systems—or if yours is already an energy efficient model—there are still things you can do to help control costs. Installing a programmable thermostat, for instance, will allow you to better manage heating and cooling, so you’re not paying to temperature control an empty house. And don’t forget to seal up your ceiling to prevent air leaks from running up your bills.

And finally, if you’re ready to upgrade your HVAC, POWER MOVES® offers rebates to help with systems that have proper AHRI certification. Find out more here.
If you’d like to learn more about how you can improve your home’s energy efficiency, contact your Energy Advisor today for a free home energy assessment.