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

December 06, 2019

While your Lennox® HVAC equipment can’t talk to you, it does have a process to get your attention when there’s a furnace error.

Its motherboard has two LED lights that can display a fault code. Subject to the malfunction, your heating system could show continuous or flashing lights.

Though there are some elementary HVAC repairs you can finish yourself, the majority of services are best handled by HVAC technicians. When your heating system won’t turn on or deliver heated air, reach out to Stephen Hurst Pack Heating and Cooling, Inc at 740-474-5940 for skilled furnace repair in Circleville.

Our specialists will quickly discover and take care of the failure, even if you don’t use a Lennox heater. We can repair all types or models—and get the warmth reintroduced to your house fast.


What Does the Blinking Light on My Heater Mean?

Your heater depends on lights to flash code when it requires repairs. It also uses this system to relay it’s working properly.

Regular heating consists of:

  • Simultaneous slow flash—heating system working like it should.
  • Both lights flash fast—furnace is initiating the call for heat.

If you see one light blinking slowly and the other flashing quickly, your furnace might have a low flame signal. This can occur even when your heating system is working correctly. It signifies the flame sensing rod might be dirty or in the incorrect area on the burner. Reach out to us at 740-474-5940 for help.

Here are a few other of the most routine errors for Lennox heaters.

Heater Will Not Kick On

Here are many of the light arrangements you might see when your heat will not or keep running. Most of these issues need to be repaired by a specialist, like one from Stephen Hurst Pack Heating and Cooling, Inc.

  1. Both LED lights are off. This signifies your HVAC system might not have power. Examine the breaker box to confirm the heater fuse hasn’t tripped. Try resetting the fuse if it is in the “off” area. If it rapidly trips following a reset, leave the breaker alone and get in touch with us us at 740-474-5940.
  2. An individual light is solid and the other is flashing slowly. This implies the flame rollout switch is possibly not working right. The switch is an important safety tool that assists in preventing fires and carbon monoxide. You shouldn’t attempt to handle this fault yourself.
  3. A single light is blinking rapidly and the other is blinking slowly. This likely means power polarity has been inverted. Your heater might have a wiring issue that calls for professional support from Stephen Hurst Pack Heating and Cooling, Inc.
  4. The duo of lights are flickering slowly. This indicates your heater’s blower motor possibly isn’t running. This part moves heated air from the HVAC system into your home. We can aid in pinpointing what’s causing a problem with this component.
  5. One light is blinking slowly and the other is flickering fast. This means your HVAC system could have low voltage or a short circuit. Reach out to our professionals at 740-474-5940 for assistance.
  6. One light is flickering on, on and off while the other blinks on, off, on. This indicates there could be a malfunction with your heating system’s motherboard or wiring. Stephen Hurst Pack Heating and Cooling, Inc can find the fault and handle it.
  7. Both lights are using alternate slow flashes. This means your heating system likely has a flame problem. There may be trouble with its gas supply, gas valve or ignitor control. Contact us at 740-474-5940 for help.
  8. A single light flashes slowly while the other remains steady. This often signifies your heating system’s limit switch is malfunctioning. The switch keeps your HVAC equipment from becoming too warm. Call the professionals at Stephen Hurst Pack Heating and Cooling, Inc for support.

Heater Blower Operates But No Heat

Here’s what may be at fault when you hear your furnace’s blower fan working, but you aren’t gaining any heated air.

  • Both lights are showing alternate quick blinks. This indicates your furnace ignitor might not be in working order. This component lights gas in your heater to make heat and should be repaired by a specialist from Stephen Hurst Pack Heating and Cooling, Inc.

Depend on Us for Expert Furnace Repair

When you need to have your heater repaired quickly, depend on the specialists at Stephen Hurst Pack Heating and Cooling, Inc. Our technicians will repair the fault right away and have your rooms feeling relaxing again in no time. Reach out to us at 740-474-5940 or contact us online to schedule an appointment right away.