What Does the Blinking Light on My Furnace Mean? - Ernst Heating & Cooling

What Does the Blinking Light on My Furnace Mean?

Blinking light on furnace

Have you ever noticed a red light on your furnace? Maybe you thought it was just an indicator light telling you all is well in Furnace Land. But if it starts blinking, your furnace is trying to tell you something. Fortunately, Ernst Heating & Cooling is fluent in furnace speak and can fix what’s wrong before you incur damage to your HVAC unit or home.

What does a blinking red light mean?

Typically, your furnace light is a solid amber or yellow color, which tells you everything’s good inside the furnace. Blinking red light means something’s not right. The trouble can range from an easy fix, like a tripped breaker switch, to something more serious, like a problem with the gas valve.

How can I tell what the furnace is trying to say?

The red light blinks in different patterns for various error codes. Your furnace may blink three times, then pause, then blink three times, and pause again. That’s code for the number 3. If it’s trying to communicate a two-digit number, it might use blinks and dashes. For instance, if your furnace is trying to convey the number 23, you’ll see blink, blink, pause, dash, dash, dash, pause. Take some time to watch the light and write down the number. You can then refer to your owner’s manual to decode the problem.

Does that sound too intimidating? It’s fine to skip the decoding process and contact Ernst Heating & Cooling to come out and take a look.

What do the various codes mean?

Codes differ by brand, where your owner’s manual comes in handy. But there is some consistency among the types of problems that prompt a blinking light. Such problems include:

Your thermostat isn’t sending a signal to the furnace. A faulty thermostat or loose wires can cause this.

Your furnace flame isn’t working. Sometimes the lighter that sends a spark to the pilot light breaks. If you see no fire in your furnace, your furnace needs immediate emergency care.

Gas valve issues. Gas issues are tricky and always require a service call. When there isn’t enough gas coming through the gas line, your furnace may not be able to light.

Circuit board failure. If your furnace’s circuit board is damaged, you need a professional, trained HVAC technician to address the problem.

Don’t ever ignore a blinking light on your furnace; reach out to Ernst Heating & Cooling at 618.217.1836 or schedule service online. Our trained HVAC technicians can decipher your furnace’s message and tackle the problem before it becomes more extensive and more costly. Remember, our goal is your family’s total comfort.

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