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

December 06, 2019

While your Lennox® furnace cannot chat with you, it does have a procedure to communicate a furnace error.

Its motherboard has double LED lights that can share a fault code. Subject to the problem, your heater might show solid or flashing lights.

While there are some elementary HVAC fixes you can do on your own, many fixes are best handled by HVAC technicians. When your heating system refuses to start or provide warmth, call Evenaire Heating & Air Conditioning at 512-355-1482 for skilled furnace repair in Pflugerville.

Our experts will quickly pinpoint and handle the problem, even if you don’t have a Lennox heater. We can service whichever kinds or configuration—and get the heat restored to your residence fast.


What Does the Flashing Light on My Heater Mean?

Your heating system uses lights to flash code when it needs to be repaired. It also works this setup to relay it’s working correctly.

Normal operation involves:

  • Concurrent slow flash—heater heating properly.
  • Concurrent fast flash—furnace is initiating the call for heat.

If you realize that one light going on and off slowly and the other going on and off quickly, your heating system might be having a low flame signal. This can take place even when your heating system is operating like it should. It signifies the flame sensing rod may be dirty or in the bad spot on the burner. Reach out to us at 512-355-1482 for assistance.

Here are some of the most common issues for Lennox heating systems.

Furnace Will Not Kick On

Here are many of the light arrangements you might notice when your furnace will not or stay on. The majority of these errors need to be repaired by a professional, for instance from Evenaire Heating & Air Conditioning.

  1. Both LED lights aren’t lit. This indicates your furnace might not have electricity. Find the breaker box to confirm the heating system fuse isn’t triggered. Attempt to reset the fuse if it is in the “off” area. If it immediately turns off after a subsequent reset, don’t try to reset it again and get in touch with us us at 512-355-1482.
  2. An individual light is stable and the other is blinking slowly. This shows the flame rollout switch is may be open. The part is a critical safety device that assists in preventing fires and carbon monoxide. You shouldn’t try to repair this problem yourself.
  3. A single light is flickering quickly and the other is flickering slowly. This likely means power polarity has been reversed. Your heating system could have a wiring fault that requires expert help from Evenaire Heating & Air Conditioning.
  4. The duo of lights are flashing slowly. This signifies your heating system’s blower motor possibly isn’t working. This piece moves warm air from the furnace into your space. We can assist in determining what’s causing a problem with this component.
  5. A single light is blinking slowly and the other is flickering quickly. This means your heating system may have low voltage or a short circuit. Get in touch with our experts at 512-355-1482 for assistance.
  6. One light is flickering on, on and off while the other flickers on, off, on. This means there might be trouble with your furnace’s control board or wiring. Evenaire Heating & Air Conditioning can determine the issue and fix it.
  7. The duo of lights are using every other slow flashes. This signifies your HVAC equipment possibly has a flame problem. There could be a problem with its gas supply, gas valve or ignitor control. Contact us at 512-355-1482 for assistance.
  8. A single light blinks slowly while the other remains solid. This typically signifies your HVAC system’s limit switch is not working. The switch keeps your HVAC equipment from getting too hot. Reach out to the specialists at Evenaire Heating & Air Conditioning for support.

Furnace Blower Operates But No Warmth

Here’s what could be broken when you notice your heating system’s blower fan running, but you aren’t getting any heat.

  • The duo of lights are showing every other rapid flashes. This signifies your furnace ignitor may not be in working order. This component ignites energy in your HVAC equipment to create warmth and should be fixed by a technician from Evenaire Heating & Air Conditioning.

Trust Us for Skilled Furnace Repair

When you need to have your HVAC equipment repaired fast, depend on the specialists at Evenaire Heating & Air Conditioning. Our techs will handle the issue quickly and have your house feeling comfortable again in no time. Contact us at 512-355-1482 or contact us online to schedule an appointment today.