Your friends told you Disco is Dead but it seems your Furnace didn’t get the memo.  

What is the story with the flashing lights?  

Do you catch yourself staring at the flashing light, in a deep trance, ready to break out into dance? 

Is your Furnace throwing a party and had the audacity not to invite you?

OR could it be, your furnace is trying to talk to you, tell you something, BUT WHAT???

Let’s break it down and Get you fluent in speaking Furnace. 

Your furnace has a control board and the lights work to alert you to various issues that your furnace wants you to address before you incur costly repairs. 

Think of these lights as built-in trouble codes that use successive flashing LED lights to indicate problems. The furnace diagnostic code lights can be seen through the furnace window or when the front panel is removed.


While Different furnace types and models have different patterns, here is a QUICK GUIDE on some TYPICAL GAS FURNACE ERROR CODES:


When the green light is flashing fast, it means you have got a working blower system and your furnace is providing heat to the home. 

If the green light is flashing slowly, it means the furnace is on but there is no request for heat. 

A continuous light likely means that the IFC circuit board needs replacing.

No light means the furnace is either off or not receiving any electrical power. It may be turned off for the season, a plug may have come loose, or the circuit is tripped.

If the light is red or not blinking, there are issues that need a closer inspection. The red light is often called a ‘lockout light’ and indicates that a safety mechanism on your furnace has caused a shutdown because it has detected a problem.

If you notice a yellow light, turn off your furnace and get in touch with a technician. A yellow light is a sign that your furnace is clogged with dirt since the amount of oxygen is being restricted. If the light goes out, that is also an indication that something is wrong with your furnace. 

Every furnace comes with a manual detailing all the different manufacturer’s codes. These codes are also often found on the back of the furnace, attached to the circuit board itself.  

If a code refers to a gas, ignition failure, or flame proving a failure, the problem is the burner assembly area, like the igniter or flame sensor, needs attention. 

It is advisable to review your furnace manual to determine what the error code is trying to communicate.  You can also contact a qualified HVAC technician to perform a full diagnostic of your furnace and reset your circuit board to clear any faulty error codes.  

We caution you not to attempt to clear the error codes simply by resetting the circuit board for the sake of ending the blinking lights.  Having a reputable, professional technician attend to the routine repairs and maintenance needs of your furnace is your best course of action.  

When you need FAST, RELIABLE, AFFORDABLE furnace service, Air In Motion will deliver.

Our highly experienced technicians will fix the issue promptly and have your furnace running efficiently again. 


Please call us at 647-921-3810 or email us at

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