Have you ever walked past your furnace and noticed a flashing light? 

You might think it is just another random indicator, but that blinking LED is actually your furnace’s way of talking to you. 

Those flashes are diagnostic codes designed to let you know when something is not quite right. 

Understanding what those signals mean can save you from bigger issues down the road.

What The Flashing Light Means

Most modern furnaces use a small LED light to show their status. When everything is working properly, you will usually see a steady glow or a slow green flash. 

However, if the light is blinking rapidly or turning red, it is your furnace’s way of signaling a problem.

For example, one or two flashes might point to an ignition failure or a problem with the pressure switch. 

Three or four flashes could mean your furnace is overheating or struggling with airflow due to a clogged filter. 

Five or more flashes may indicate more serious issues, like a faulty flame sensor or gas valve trouble.

How To Troubleshoot Simple Issues

Before you call for help, there are a few quick things you can safely check. Start with the air filter. 

A dirty or clogged filter is one of the most common causes of furnace issues in Colorado homes. Replacing it can often solve the problem and help your system breathe easier.

Next, check your thermostat. Make sure the batteries are working and the settings are correct. If your furnace uses gas, confirm the gas valve is in the “on” position. 

Finally, take a look at the vent pipes outside your home. Snow, leaves, or small animal nests can block airflow and cause your furnace to flash error codes.

Trust Local Experts To Keep You Warm

Here in Northern Colorado, where winters can get chilly fast, a reliable furnace is essential. The experienced technicians at SWAN Plumbing, Heating & Air Conditioning, INC understand how local weather affects your system’s performance. 

We are familiar with the most common furnace issues homeowners in Fort Collins and nearby areas face, and we know how to fix them efficiently.

If your furnace light is flashing and you are not sure why, let our experts handle it. Contact SWAN Plumbing, Heating & Air Conditioning, INC today for professional furnace diagnostics and repairs that keep your home safe, warm, and comfortable all winter long.