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

December 06, 2019

While your Lennox® furnace cannot chat with you, it possesses a process to communicate a furnace error.

Its control board has a set of LED lights that can show a fault code. Subject to the issue, your furnace could show steady or flashing lights.

Though there are certain elementary furnace fixes you can complete without an expert, many services are best left to experts. When your heating system won’t kick on or put out warmth, get in touch with Appalachian Heating at 304-707-0600 for skilled furnace repair in Beckley and Mount Hope.

Our technicians will quickly detect and take care of the issue, even if you don’t use a Lennox heating system. We can repair whichever types or makes—and get the heat restored to your home without delay.


What Does the Flickering Light on My Furnace Mean?

Your heater uses lights to flash code when it needs to be repaired. It also works this setup to tell you it’s heating like it should.

Normal operation involves:

  • Simultaneous slow flash—heating system operating like it should.
  • Both lights flash fast—heating system is starting to call for heat.

If you realize that a single light going on and off slowly and the other flashing quickly, your heater might be having a low flame signal. This can happen even when your heating system is running correctly. It means the flame sensing rod might have build-up or in the incorrect location on the burner. Call us at 304-707-0600 for help.

Here are several other of the most typical problems for Lennox heaters.

Furnace Won’t Turn On

Here are a few of the light arrangements you may notice when your heater won’t turn on or keep operating. The majority of these errors have to be taken care of by a technician, for instance from Appalachian Heating.

  1. Both LED lights aren’t lit. This means your HVAC system might not have electricity. Look at the breaker box to ensure the heater fuse is not triggered. Try resetting the fuse if it is in the “off” spot. If it immediately flips after a subsequent reset, don’t touch the breaker and call us at 304-707-0600.
  2. An individual light is continuous and the other is blinking slowly. This implies the flame rollout switch is possibly malfunctioning. The part is an important safety guard that aids in stopping fires and carbon monoxide. You shouldn’t attempt to fix this malfunction yourself.
  3. A single light is flashing fast and the other is blinking slowly. This likely signifies power polarity has been inverted. Your furnace could have a wiring fault that calls for professional aid from Appalachian Heating.
  4. The pair of lights are flickering slowly. This signifies your heater’s blower motor likely isn’t working. This part circulates warm air from the heating system into your space. We can assist in determining what’s causing a problem with this part.
  5. An individual light is flashing slowly and the other is flashing quickly. This signifies your heater could have not enough voltage or a short circuit. Call our experts at 304-707-0600 for assistance.
  6. One light is flickering on, on and off while the other blinks on, off, on. This means there might be an error with your HVAC system’s motherboard or wiring. Appalachian Heating can locate the issue and handle it.
  7. The duo of lights display alternating slow flickers. This means your furnace may have a flame issue. There could be an issue with its gas supply, gas valve or ignitor control. Reach out to us at 304-707-0600 for assistance.
  8. An individual light blinks slowly while the other stays steady. This usually indicates your HVAC equipment’s limit switch is malfunctioning. The switch keeps your heating system from getting too hot. Get in touch with the pros at Appalachian Heating for assistance.

Heating System Blower Works But No Heat

Here’s what could be broken when you notice your heater’s blower fan running, but you aren’t getting any warm air.

  • Both lights are showing alternating fast flickers. This signifies your furnace ignitor may not be in working order. This part lights gas in your heating system to produce warmth and should be fixed by a technician from Appalachian Heating.

Trust Us for Professional Furnace Repair

When you have to have your heater fixed fast, turn to the professionals at Appalachian Heating. Our pros will fix the fault promptly and have your rooms feeling relaxing again in no time. Contact us at 304-707-0600 or contact us online to request an appointment right away.