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

December 06, 2019

While your Lennox® HVAC equipment cannot talk to you, it has a procedure to get your attention when there’s a furnace error.

Its control board has two LED lights that can show a fault code. Depending on the issue, your furnace could show continuous or flashing lights.

While there are some elementary heating repairs you can finish yourself, most repairs are best handled by HVAC technicians. When your furnace will not kick on or provide heated air, contact Walter's-Eaton's Electric, Plumbing, Heating & AC at 715-318-6728 for expert furnace repair in Ellsworth.

Our experts will swiftly determine and handle the fault, even if you don’t use a Lennox heating system. We can repair any types or models—and get the comfort returned to your house without delay.


What Does the Flashing Light on My Furnace Mean?

Your heater relies on lights to flash code when it requires repairs. It also works this system to tell you it’s operating like it should.

Normal heating includes:

  • Simultaneous slow flash—heating system operating like it should.
  • Simultaneous fast flash—heater is starting to call for heat.

If you realize that one light going on and off slowly and the other going on and off quickly, your furnace might be experiencing a low flame signal. This can occur even when your heater is running properly. It means the flame sensing rod might be dirty or in the wrong spot on the burner. Contact us at 715-318-6728 for help.

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

Heating System Won’t Kick On

Here are a few of the light patterns you may notice when your heat won’t turn on or keep running. The bulk of these problems must be repaired by a technician, for instance from Walter's-Eaton's Electric, Plumbing, Heating & AC.

  1. The pair of LED lights are off. This indicates your heating system might not have electricity. Check the breaker box to ensure the heating system fuse has not triggered. Attempt to reset the fuse if it is in the “off” area. If it promptly flips following a reset, leave the breaker alone and get in touch with us us at 715-318-6728.
  2. One light is stable and the other is blinking slowly. This signifies the flame rollout switch is may be malfunctioning. The component is a critical safety device that helps in stopping fires and carbon monoxide. You shouldn’t attempt to handle this problem on your own.
  3. A single light is flashing rapidly and the other is flashing slowly. This usually indicates power polarity has been transposed. Your heating system might have a wiring issue that requires specialized assistance from Walter's-Eaton's Electric, Plumbing, Heating & AC.
  4. The duo of lights are blinking slowly. This means your heater’s blower motor likely isn’t operating. This piece sends warm air from the furnace into your space. We can aid in figuring out what’s wrong with this piece.
  5. An individual light is flashing slowly and the other is flashing rapidly. This means your heater could have low voltage or a short circuit. Reach out to our experts at 715-318-6728 for assistance.
  6. One light is flickering on, on and off while the other blinks on, off, on. This means there could be trouble with your furnace’s control panel or wiring. Walter's-Eaton's Electric, Plumbing, Heating & AC can determine the problem and fix it.
  7. Both lights display every other slow flickers. This means your heater possibly has a flame failure. There may be trouble with its gas supply, gas valve or ignitor control. Get in touch with us at 715-318-6728 for support.
  8. An individual light flickers slowly while the other is solid. This usually signifies your furnace’s limit switch is not working. The switch keeps your heating system from overheating. Call the specialists at Walter's-Eaton's Electric, Plumbing, Heating & AC for help.

Heating System Blower Operates But No Warm Air

Here’s what might be wrong when you hear your furnace’s blower fan running, but you aren’t gaining any heated air.

  • Both lights display alternate quick blinks. This indicates your furnace ignitor may not be working. This piece ignites energy in your furnace to create warm air and should be repaired by a professional from Walter's-Eaton's Electric, Plumbing, Heating & AC.

Trust Us for Expert Furnace Repair

When you have to have your heating system repaired without delay, trust the specialists at Walter's-Eaton's Electric, Plumbing, Heating & AC. Our pros will repair the issue without delay and have your rooms feeling cozy again in no time. Contact us at 715-318-6728 or contact us online to get an appointment today.