Top Lennox® Furnace Error Codes (and What They Mean)

December 06, 2019

While your Lennox® heating system isn’t able to chat with you, it possesses a procedure to get your attention when there’s a furnace error.

Its control board has twin LED lights that can show a fault code. Subject to the fault, your heating system could display steady or flashing lights.

Although there are various simple HVAC adjustments you can do without an expert, many services are best left to experts. When your furnace refuses to start or provide heated air, call James Heating & A/C, Inc at 336-853-6070 for experienced furnace repair in Lexington.

Our technicians will speedily spot and handle the fault, even if you don’t use a Lennox heating system. We can fix whichever kinds or models—and get the warmth returned to your residence fast.


What Does the Flashing Light on My Furnace Mean?

Your furnace relies on lights to flash code when it isn’t working right. It also uses this system to relay it’s running correctly.

Normal operation consists of:

  • Simultaneous slow flash—heater running like it should.
  • Both lights flash fast—furnace is beginning to call for heat.

If you notice a single light going on and off slowly and the other blinking fast, your heater might have a low flame signal. This can occur even when your heating system is working like it should. It means the flame sensing rod may have build-up or in the wrong area on the burner. Call us at 336-853-6070 for help.

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

Furnace Refuses to Turn On

Here are many of the light patterns you might see when your furnace refuses to or keep running. Most of these problems must be taken care of by a specialist, for instance from James Heating & A/C, Inc.

  1. The pair of LED lights are off. This indicates your HVAC system might not be receiving power. Examine the breaker box to confirm the heater fuse isn’t triggered. Attempt to reset the fuse if it is in the “off” position. If it promptly turns off after you reset it, don’t try to reset it again and get in touch with us us at 336-853-6070.
  2. An individual light is continuous and the other is blinking slowly. This means the flame rollout switch is possibly malfunctioning. The switch is an important safety mechanism that aids in avoiding fires and carbon monoxide. You shouldn’t attempt to fix this issue without professional help.
  3. A single light is flashing rapidly and the other is flashing slowly. This usually means power polarity has been reversed. Your heater may have a wiring error that calls for specialized help from James Heating & A/C, Inc.
  4. All lights are blinking slowly. This indicates your furnace’s blower motor probably isn’t running. This component sends hot air from the furnace into your house. We can aid in determining what’s wrong with this component.
  5. An individual light is flashing slowly and the other is flashing fast. This indicates your heater may have insufficient voltage or a short circuit. Reach out to our professionals at 336-853-6070 for support.
  6. One light is blinking on, on and off while the other flickers on, off, on. This means there could be a problem with your heater’s control board or wiring. James Heating & A/C, Inc can find the error and handle it.
  7. The duo of lights show alternate slow flashes. This means your heater may have a flame issue. There may be an issue with its gas supply, gas valve or ignitor control. Reach out to us at 336-853-6070 for assistance.
  8. An individual light flickers slowly while the other stays steady. This often signifies your heater’s limit switch is malfunctioning. The switch keeps your heater from overheating. Reach out to the experts at James Heating & A/C, Inc for assistance.

Heater Blower Works But No Warm Air

Here’s what might be wrong when you observe your heating equipment’s blower fan on, but you aren’t gaining any warm air.

  • Both lights display alternating quick flickers. This signifies your furnace ignitor may not be working. This piece kindles energy in your heater to make heat and should be serviced by a professional from James Heating & A/C, Inc.

Trust Us for Expert Furnace Repair

When you need to get your HVAC equipment in working order quickly, trust the specialists at James Heating & A/C, Inc. Our pros will handle the issue right away and have your rooms feeling relaxing again soon. Contact us at 336-853-6070 or contact us online to get an appointment now.