How Does My Furnace Work?

turning the heat up.

Why should you care how a furnace works? Because if your furnace ever fails to run, knowing the basics might come in handy.

Around Texas, when people need heat, most people rely on gas furnaces to heat their homes. You adjust the thermostat, the furnace kicks on, and warm air blows from the vent. Life is good.

But when it fails to turn on, you have a problem. Understanding how a furnace works and some of the most common reasons it fails is always helpful knowledge.

Trust your team at AiRCO Heating and Cooling to maintain your heating, ventilation, and air conditioning (HVAC) system throughout the year. We value your comfort and well-being here in Austin.

Meet the Thermostat

While the furnace gets the most attention on the HVAC team during the colder season, the thermostat runs the show. A thermostat is a temperature-activated switch that works with the furnace control board. Once you program your thermostat to a particular temperature, your HVAC system will cycle on and off to keep your home near that set level.

When your thermostat sends a signal to your gas furnace to turn on your heating system, the first thing that happens is your ignitor starts. The ignitor lights the fuel in the combustion chamber, and a blower distributes warm air into your house through air ducts.

Most furnaces today have electronic starters to ignite the gas burner, while older furnaces rely on standing pilot lights. A gas pilot light should be brightblue with a hint of yellow at the tip of the flameA flickering or yellow pilot light could indicate excessive carbon monoxide or a failing  igniter.

The Combustion Chamber 

The draft hood or vent system in your furnace takes in oxygen to generate clean and efficient combustion. This same vent system releases the combustion byproducts through a flue to the outside air.

Properly maintaining your combustion chamber is important to ensure your indoor air quality is safe and healthy.

Bring the Heat!

The heat exchanger in your furnace takes the heat that rises above the chamber to generate warm air for your home. Heat exchangers typically use a series of metal tubes that are heated by burners when gas is ignited inside the combustion chamber.

These hot tubes transfer radiant heat to the air that blows through the exchanger. Once the air reaches the proper temperature, the furnace blower turns on to distribute it throughout your air duct system. When the cooler air returns to the furnace, the entire cycle begins again.

Trust our professionals at AiRCO Heating and Air Conditioning to keep your heat exchanger in good working order. A cracked heat exchanger is a major risk of carbon monoxide leaking and can be deadly.  Legally our team is required to shut down and disable a furnace with a cracked heat exchanger for the safety of everyone in your home.

Furnace Maintenance Tips

We recommend changing your air filter every three months or more if necessary. A clogged air filter slows down your furnace, forces all the components to work that much harder, and could eventually lead to a costly repair.

Always check the thermostat battery if your furnace isn’t responding when you adjust the temperature. Switching out the thermostat battery can sometimes solve the issue.

Sealing and insulating your ductwork can improve your HVAC energy efficiency up to 20 percent, according to ENERGY STAR®. 

Contact Us for All Your Furnace Needs

Count on AiRCO in Austin, TX, to address your HVAC needs. Our team of experienced professionals can help keep your furnace operating at peak efficiency. Call 313.401.3014 or request service online today to learn more about furnaces and how they work.

Need HVAC Service?

Contact the experts at AiRCO Mechanical.

Call us at 512-537-1234!

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