Furnace troubleshooting

Most Common Lennox® Furnace Error Codes (and What They Mean)

While your Lennox® heating system isn’t able to talk to you, it possesses a procedure to communicate a furnace error.

Its motherboard has two LED lights that can display a fault code. Depending on the problem, your furnace might show continuous or flashing lights.

Although there are a few simple heating adjustments you can take care of on your own, many fixes are best left to experts. When your heating system won’t start or provide heat, get in touch with Alan Heating Air Conditioning, Inc. at 630-833-1100 for professional furnace repair in Elmhurst.

Our specialists will rapidly identify and fix the issue, even if you don’t own a Lennox heater. We can fix all types or models—and get the comfort reintroduced to your house quickly.


What Does the Flickering Light on My Heating System Mean?

Your furnace relies on lights to flash code when it needs to be repaired. It also works these lights to let you know it’s running like it should.

Normal operation consists of:

  • Both lights flash slowly—heating system running properly.
  • Concurrent fast flash—heater is starting to call for heat.

If you realize that a single light blinking slowly and the other flashing quickly, your furnace might have a low flame signal. This can occur even when your furnace is heating correctly. It means the flame sensing rod could be dirty or in the wrong spot on the burner. Reach out to us at 630-833-1100 for assistance.

Here are several other of the most common errors for Lennox heaters.

Heating System Will Not Turn On

Here are many of the light arrangements you may see when your heating system refuses to or keep operating. The majority of these errors must be repaired by a professional, such as one from Alan Heating Air Conditioning, Inc..

  1. All LED lights aren’t lit. This signifies your HVAC system might not have power. Look at the breaker box to make sure the heating system fuse has not triggered. You should reset the fuse if it’s in the “off” spot. If it promptly trips following a reset, leave the breaker alone and contact us at 630-833-1100.
  2. One light is unchanging and the other is flashing slowly. This means the flame rollout switch is likely not working right. The part is an important safety mechanism that aids in avoiding fires and carbon monoxide. You shouldn’t attempt to repair this malfunction without professional help.
  3. One light is flickering quickly and the other is flashing slowly. This usually indicates power polarity has been reversed. Your heating system could have a wiring fault that calls for expert support from Alan Heating Air Conditioning, Inc..
  4. Both lights are flickering slowly. This indicates your furnace’s blower motor probably isn’t working. This component moves heated air from the heating system into your space. We can assist in figuring out what’s causing an issue with this piece.
  5. One light is blinking slowly and the other is flashing quickly. This signifies your heating system may have low voltage or a short circuit. Call our experts at 630-833-1100 for help.
  6. One light is blinking on, on and off while the other flickers on, off, on. This signifies there may be a malfunction with your heater’s motherboard or wiring. Alan Heating Air Conditioning, Inc. can determine the fault and handle it.
  7. The duo of lights show alternating slow flashes. This signifies your heating system possibly has a flame failure. There may be a problem with its gas supply, gas valve or ignitor control. Get in touch with us at 630-833-1100 for support.
  8. One light blinks slowly while the other is continuous. This usually indicates your HVAC system’s limit switch is open. The switch stops your heating system from getting too hot. Contact the specialists at Alan Heating Air Conditioning, Inc. for support.

Furnace Blower Runs But No Warm Air

Here’s what may be at fault when you hear your heating equipment’s blower fan working, but you aren’t getting any heat.

  • Both lights are showing alternate rapid flickers. This signifies your furnace ignitor might be broken. This component kindles energy in your furnace to produce warmth and should be repaired by a professional from Alan Heating Air Conditioning, Inc..

Depend on Us for Professional Furnace Repair

When you need to get your heating system in working order quickly, turn to the technicians at Alan Heating Air Conditioning, Inc.. Our pros will repair the error quickly and have your space feeling comfortable again in no time. Get in touch with us at 630-833-1100 or contact us online to request an appointment now.

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