Furnace troubleshooting

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

While your Lennox® heater isn’t able to chat with you, it has a way to get your attention when there’s a furnace error.

Its control board has a set of LED lights that can display a fault code. Subject to the problem, your furnace could use continuous or flashing lights.

While there are certain elementary HVAC adjustments you can complete on your own, most tasks are best taken care of by HVAC technicians. When your furnace will not start or put out heat, reach out to AW Heating & Air Conditioning at 402-318-5351 for skilled furnace repair in Lincoln.

Our experts will quickly spot and fix the malfunction, even if you don’t own a Lennox furnace. We can service all types or configuration—and get the comfort returned to your home without delay.


What Does the Blinking Light on My Heater Mean?

Your heater relies on lights to flash code when it requires repairs. It also works this system to let you know it’s heating correctly.

Normal heating involves:

  • Concurrent slow flash—furnace operating correctly.
  • Both lights flash fast—heating system is starting to call for heat.

If you notice one light flashing slowly and the other going on and off quickly, your furnace might have a low flame signal. This can happen even when your furnace is running correctly. It signifies the flame sensing rod might be dirty or in the incorrect area on the burner. Reach out to us at 402-318-5351 for assistance.

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

Furnace Won’t Turn On

Here are many of the light sequences you might observe when your heater will not or stay on. The majority of these problems need to be handled by an expert, for instance from AW Heating & Air Conditioning.

  1. All LED lights are off. This indicates your heater might not have electricity. Go to the breaker box to confirm the heater fuse hasn’t triggered. Attempt to reset the fuse if it’s in the “off” area. If it rapidly flips after you reset it, don’t try to reset it again and contact us at 402-318-5351.
  2. An individual light is stable and the other is flickering slowly. This signifies the flame rollout switch is likely open. The component is an essential safety guard that assists in preventing fires and carbon monoxide. You shouldn’t try to fix this issue on your own.
  3. An individual light is flickering fast and the other is flashing slowly. This likely indicates power polarity has been reversed. Your heating system could have a wiring problem that needs specialized help from AW Heating & Air Conditioning.
  4. The duo of lights are flickering slowly. This means your heating system’s blower motor likely isn’t working. This part moves hot air from the HVAC system into your space. We can aid in figuring out what’s causing a problem with this piece.
  5. One light is flashing slowly and the other is blinking fast. This means your heating system might have low voltage or a short circuit. Get in touch with our professionals at 402-318-5351 for assistance.
  6. One light is flashing on, on and off while the other flickers on, off, on. This signifies there may be a malfunction with your HVAC system’s motherboard or wiring. AW Heating & Air Conditioning can determine the error and fix it.
  7. The duo of lights display alternating slow flickers. This indicates your heating system possibly has a flame issue. There might be an issue with its gas supply, gas valve or ignitor control. Call us at 402-318-5351 for assistance.
  8. An individual light flickers slowly while the other is steady. This typically indicates your heating system’s limit switch is malfunctioning. The switch keeps your heating system from becoming too warm. Contact the experts at AW Heating & Air Conditioning for assistance.

Furnace Blower Runs But No Warm Air

Here’s what could be wrong when you notice your heating system’s blower fan working, but you aren’t gaining any warmth.

  • The pair of lights are showing alternate quick blinks. This means your furnace ignitor may not be working. This piece ignites energy in your furnace to create heat and should be repaired by an expert from AW Heating & Air Conditioning.

Trust Us for Skilled Furnace Repair

When you have to get your heating system repaired fast, trust the technicians at AW Heating & Air Conditioning. Our technicians will fix the problem promptly and have your residence feeling relaxing again in no time. Get in touch with us at 402-318-5351 or contact us online to schedule an appointment now.

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