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

December 06, 2019

While your Lennox® HVAC equipment can’t chat with you, it has a method to get your attention when there’s a furnace error.

Its control board has two LED lights that can display a fault code. Depending on the problem, your furnace might display steady or flashing lights.

Although there are some elementary heating adjustments you can finish on your own, many services are best handled by experts. When your heating system refuses to turn on or provide heat, call Giordanos Heating and Air Conditioning at 203-772-8319 for expert furnace repair in Derby.

Our experts will swiftly determine and handle the issue, even if you don’t have a Lennox furnace. We can service whichever kinds or makes—and get the warmth returned to your residence fast.


What Does the Blinking Light on My Furnace Mean?

Your heating system relies on lights to flash code when it requires repairs. It also engages these lights to relay it’s operating like it should.

Normal operation includes:

  • Concurrent slow flash—heating system working like it should.
  • Both lights flash fast—heater is starting to call for heat.

If you realize that a solitary light flashing slowly and the other going on and off quickly, your heater might be experiencing a low flame signal. This can take place even when your furnace is running like it should. It signifies the flame sensing rod could have build-up or in the incorrect spot on the burner. Contact us at 203-772-8319 for help.

Here are several other of the most common issues for Lennox HVAC systems.

Heating System Won’t Kick On

Here are a few of the light patterns you might notice when your heat will not or stay on. The majority of these problems need to be handled by a professional, such as one from Giordanos Heating and Air Conditioning.

  1. Both LED lights aren’t lit. This indicates your heater might not have electricity. Find the breaker box to confirm the furnace fuse has not triggered. You should reset the fuse if it has moved into the “off” area. If it promptly turns off after you reset it, don’t try to reset it again and contact us at 203-772-8319.
  2. An individual light is stable and the other is flashing slowly. This signifies the flame rollout switch is may be open. The component is a critical safety device that assists in avoiding fires and carbon monoxide. You shouldn’t attempt to fix this issue yourself.
  3. A single light is blinking fast and the other is blinking slowly. This usually means power polarity has been transposed. Your furnace may have a wiring issue that needs expert support from Giordanos Heating and Air Conditioning.
  4. The pair of lights are flickering slowly. This indicates your furnace’s blower motor likely isn’t running. This part circulates heated air from the HVAC system into your residence. We can help in figuring out what’s wrong with this piece.
  5. An individual light is flickering slowly and the other is flickering quickly. This means your HVAC system might have not enough voltage or a short circuit. Reach out to our experts at 203-772-8319 for help.
  6. One light is blinking on, on and off while the other blinks on, off, on. This indicates there may be a problem with your heater’s control panel or wiring. Giordanos Heating and Air Conditioning can pinpoint the issue and repair it.
  7. The pair of lights are using every other slow blinks. This signifies your heater likely has a flame issue. There may be trouble with its gas supply, gas valve or ignitor control. Reach out to us at 203-772-8319 for assistance.
  8. One light flickers slowly while the other stays solid. This typically signifies your heating system’s limit switch is open. The switch prevents your HVAC equipment from becoming too warm. Reach out to the specialists at Giordanos Heating and Air Conditioning for assistance.

Furnace Blower Runs But No Warmth

Here’s what could be at fault when you hear your heater’s blower fan working, but you aren’t receiving any heated air.

  • The duo of lights are showing alternate quick flashes. This means your furnace ignitor may not be in working order. This part lights fuel in your heater to create heat and should be repaired by a specialist from Giordanos Heating and Air Conditioning.

Trust Us for Skilled Furnace Repair

When you need to have your HVAC equipment in working order quickly, trust the professionals at Giordanos Heating and Air Conditioning. Our pros will fix the issue quickly and have your home feeling relaxing again soon. Call us at 203-772-8319 or contact us online to request an appointment today.