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

December 06, 2019

While your Lennox® heater cannot chat with you, it does have a method to communicate a furnace error.

Its control board has double LED lights that can show a fault code. Depending on the malfunction, your heating system may show solid or flashing lights.

Although there are some simple heating fixes you can finish yourself, most tasks are best handled by HVAC technicians. When your furnace will not start or deliver heated air, reach out to Taylor's Heating & Air Conditioning at 519-296-4437 for skilled furnace repair in Thedford.

Our technicians will rapidly pinpoint and handle the issue, even if you don’t have a Lennox heating system. We can repair whichever kinds or makes—and get the heat returned to your residence quickly.


What Does the Flashing Light on My Furnace Mean?

Your heater uses lights to flash code when it is malfunctioning. It also uses this setup to let you know it’s running properly.

Regular heating involves:

  • Concurrent slow flash—furnace working like it should.
  • Concurrent fast flash—furnace is initiating the call for heat.

If you notice a single light going on and off slowly and the other flashing rapidly, your heating system might be having a low flame signal. This can happen even when your heating system is operating correctly. It signifies the flame sensing rod may have build-up or in the bad spot on the burner. Reach out to us at 519-296-4437 for help.

Here are some of the most routine problems for Lennox HVAC systems.

Furnace Will Not Turn On

Here are many of the light sequences you may observe when your furnace refuses to or keep running. Most of these issues must be fixed by a specialist, for instance from Taylor's Heating & Air Conditioning.

  1. The pair of LED lights aren’t lit. This signifies your furnace might not have power. Check the breaker box to confirm the furnace fuse hasn’t flipped. Attempt to reset the fuse if it is in the “off” spot. If it promptly turns off following a reset, don’t try to reset it again and get in touch with us us at 519-296-4437.
  2. An individual light is stable and the other is blinking slowly. This shows the flame rollout switch is likely not working right. The component is an essential safety device that helps in avoiding fires and carbon monoxide. You shouldn’t try to take care of this fault on your own.
  3. One light is blinking quickly and the other is blinking slowly. This typically means power polarity has been inverted. Your furnace may have a wiring problem that needs professional support from Taylor's Heating & Air Conditioning.
  4. Both lights are blinking slowly. This indicates your heater’s blower motor probably isn’t operating. This part circulates warm air from the furnace into your space. We can assist in figuring out what’s causing an issue with this part.
  5. One light is blinking slowly and the other is flickering rapidly. This means your heating system may have low voltage or a short circuit. Reach out to our experts at 519-296-4437 for assistance.
  6. One light is flashing on, on and off while the other blinks on, off, on. This means there might be trouble with your heater’s motherboard or wiring. Taylor's Heating & Air Conditioning can determine the fault and take care of it.
  7. The duo of lights show alternate slow blinks. This signifies your HVAC system may have a flame problem. There may be an issue with its gas supply, gas valve or ignitor control. Get in touch with us at 519-296-4437 for support.
  8. An individual light blinks slowly while the other stays steady. This usually signifies your heater’s limit switch is not working. The switch prevents your heating system from getting too hot. Reach out to the pros at Taylor's Heating & Air Conditioning for assistance.

Heater Blower Operates But No Heat

Here’s what might be broken when you hear your heater’s blower fan working, but you aren’t receiving any heated air.

  • The pair of lights are giving every other fast flashes. This signifies your furnace ignitor may not be working. This component lights gas in your heater to make warmth and should be fixed by a specialist from Taylor's Heating & Air Conditioning.

Trust Us for Expert Furnace Repair

When you have to have your heater in working order without delay, turn to the technicians at Taylor's Heating & Air Conditioning. Our pros will handle the fault promptly and have your residence feeling relaxing again in no time. Contact us at 519-296-4437 or contact us online to get an appointment today.