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

December 06, 2019

While your Lennox® heater can’t chat with you, it possesses a procedure to get your attention when there’s a furnace error.

Its motherboard has twin LED lights that can share a fault code. Based on the failure, your heating system could use steady or flashing lights.

While there are a few basic heating fixes you can finish yourself, many tasks are best taken care of by experts. When your heater refuses to start or provide warmth, contact Davis Heating & Air Conditioning at 540-369-3790 for expert furnace repair in Rocky Mount.

Our technicians will swiftly diagnose and handle the issue, even if you don’t own a Lennox furnace. We can repair all kinds or makes—and get the heat reintroduced to your house fast.


What Does the Blinking Light on My Heater Mean?

Your furnace relies on lights to flash code when it requires repairs. It also engages these lights to tell you it’s heating properly.

Regular function includes:

  • Concurrent slow flash—heater running properly.
  • Both lights flash fast—heating system is starting to call for heat.

If you see a lone light going on and off slowly and the other blinking rapidly, your heater might have a low flame signal. This can happen even when your heater is working correctly. It indicates the flame sensing rod may have build-up or in the incorrect location on the burner. Reach out to us at 540-369-3790 for support.

Here are some of the most typical issues for Lennox HVAC systems.

Heater Will Not Turn On

Here are a few of the light sequences you may notice when your furnace will not or stay on. The majority of these issues need to be repaired by an expert, such as one from Davis Heating & Air Conditioning.

  1. The duo of LED lights are extinguished. This signifies your heater might not have electricity. Examine the breaker box to confirm the heater fuse has not tripped. You should reset the fuse if it is in the “off” area. If it instantly trips after you reset it, don’t touch the breaker and get in touch with us us at 540-369-3790.
  2. An individual light is continuous and the other is flashing slowly. This shows the flame rollout switch is possibly malfunctioning. The part is a critical safety guard that helps in preventing fires and carbon monoxide. You shouldn’t attempt to take care of this problem yourself.
  3. One light is flickering fast and the other is blinking slowly. This likely indicates power polarity has been reversed. Your heating system could have a wiring fault that calls for professional aid from Davis Heating & Air Conditioning.
  4. All lights are blinking slowly. This signifies your heater’s blower motor possibly isn’t working. This part distributes heated air from the furnace into your space. We can assist in pinpointing what’s causing an issue with this piece.
  5. A single light is blinking slowly and the other is blinking quickly. This signifies your heater might have insufficient voltage or a short circuit. Get in touch with our professionals at 540-369-3790 for help.
  6. One light is flashing on, on and off while the other flashes on, off, on. This indicates there might be a problem with your furnace’s motherboard or wiring. Davis Heating & Air Conditioning can pinpoint the problem and repair it.
  7. Both lights are using alternate slow flickers. This signifies your HVAC equipment possibly has a flame problem. There may be an issue with its gas supply, gas valve or ignitor control. Get in touch with us at 540-369-3790 for help.
  8. One light blinks slowly while the other stays steady. This typically indicates your heater’s limit switch is malfunctioning. The switch keeps your furnace from overheating. Call the professionals at Davis Heating & Air Conditioning for support.

Furnace Blower Operates But No Warmth

Here’s what might be wrong when you hear your heater’s blower fan on, but you aren’t getting any warmth.

  • The duo of lights are giving alternate rapid flickers. This means your furnace ignitor might not be in working order. This component ignites gas in your furnace to make warm air and should be serviced by a professional from Davis Heating & Air Conditioning.

Trust Us for Skilled Furnace Repair

When you have to have your heater in working order fast, trust the technicians at Davis Heating & Air Conditioning. Our pros will fix the issue promptly and have your house feeling cozy again soon. Contact us at 540-369-3790 or contact us online to get an appointment today.