Furnace troubleshooting

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

While your Lennox® heating system isn’t able to speak to you, it has a way to communicate a furnace error.

Its control board has twin LED lights that can display a fault code. Depending on the fault, your heater may display continuous or flashing lights.

Though there are certain basic heating fixes you can take care of on your own, most services are best handled by the professionals. When your furnace won’t kick on or deliver heated air, call Northglenn Heating & Air Conditioning, Inc. at 303-452-4146 for skilled furnace repair in Northglenn.

Our technicians will rapidly identify and fix the malfunction, even if you don’t own a Lennox furnace. We can fix whichever brands or models—and get the warmth reintroduced to your residence fast.


What Does the Flickering Light on My Furnace Mean?

Your heater depends on lights to flash code when it isn’t working right. It also uses these lights to let you know it’s working like it should.

Correct function includes:

  • Concurrent slow flash—heating system heating like it should.
  • Simultaneous fast flash—heating system is initiating the call for heat.

If you notice a solitary light blinking slowly and the other going on and off quickly, your heater could be having a low flame signal. This can take place even when your heating system is running correctly. It indicates the flame sensing rod may need to be cleaned or in the wrong area on the burner. Call us at 303-452-4146 for assistance.

Here are several other of the most routine errors for Lennox furnaces.

Heating System Refuses to Start

Here are many of the light arrangements you might observe when your heat will not or keep heating. The majority of these problems have to be taken care of by a specialist, such as one from Northglenn Heating & Air Conditioning, Inc..

  1. Both LED lights are off. This indicates your furnace might not have electricity. Go to the breaker box to make sure the heating system fuse is not flipped. Try resetting the fuse if it is in the “off” area. If it immediately trips following a reset, leave the breaker alone and call us at 303-452-4146.
  2. One light is stable and the other is blinking slowly. This signifies the flame rollout switch is likely malfunctioning. The component is an essential safety tool that helps in stopping fires and carbon monoxide. You shouldn’t seek to repair this problem yourself.
  3. An individual light is flashing fast and the other is flickering slowly. This often signifies power polarity has been reversed. Your heater may have a wiring error that needs professional help from Northglenn Heating & Air Conditioning, Inc..
  4. The pair of lights are flickering slowly. This indicates your furnace’s blower motor probably isn’t working. This piece distributes hot air from the heater into your space. We can aid 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 heating system might have not enough voltage or a short circuit. Contact our technicians at 303-452-4146 for assistance.
  6. One light is blinking on, on and off while the other flickers on, off, on. This indicates there might be a fault with your HVAC system’s motherboard or wiring. Northglenn Heating & Air Conditioning, Inc. can pinpoint the issue and take care of it.
  7. Both lights show every other slow flickers. This means your HVAC 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 303-452-4146 for support.
  8. A single light blinks slowly while the other is continuous. This often means your heater’s limit switch is experiencing an error. The switch stops your HVAC equipment from overheating. Get in touch with the experts at Northglenn Heating & Air Conditioning, Inc. for assistance.

Heating System Blower Operates But No Warmth

Here’s what might be broken when you observe your heating system’s blower fan running, but you aren’t getting any heated air.

  • The duo of lights display every other quick blinks. This indicates your furnace ignitor could not be working. This component ignites energy in your furnace to create warmth and should be repaired by a specialist from Northglenn Heating & Air Conditioning, Inc..

Trust Us for Skilled Furnace Repair

When you have to get your HVAC equipment fixed quickly, turn to the specialists at Northglenn Heating & Air Conditioning, Inc.. Our techs will fix the problem without delay and have your house feeling comfortable again in a short time. Reach out to us at 303-452-4146 or contact us online to get an appointment today.

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