Furnace troubleshooting

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

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

Its control board has twin LED lights that can display a fault code. Depending on the fault, your heater may show continuous or flashing lights.

Although there are certain basic heating fixes you can take care of on your own, the majority of services are best left to the professionals. When your furnace won’t start or deliver heated air, call Northglenn Heating & Air Conditioning, Inc. at 303-452-4146 for skilled furnace repair in Northglenn.

Our technicians will rapidly discover and fix the malfunction, even if you don’t own a Lennox furnace. We can fix whichever brands or makes—and get the warmth reintroduced to your residence fast.


What Does the Flickering Light on My Furnace Mean?

Your heater depends on lights to flash code when it isn’t working right. It also uses these lights to let you know it’s working like it should.

Regular function includes:

  • Simultaneous slow flash—heating system heating properly.
  • Simultaneous fast flash—furnace is initiating the call for heat.

If you notice one light blinking slowly and the other blinking quickly, your heater could be having a low flame signal. This can occur even when your heater is running correctly. It indicates the flame sensing rod could need to be cleaned or in the incorrect area on the burner. Call us at 303-452-4146 for assistance.

Here are some of the most routine errors for Lennox heating systems.

Heater Refuses to Kick On

Here are a few of the light arrangements you might observe when your heat will not or stay on. The majority of these issues have to be taken care of by a specialist, like one from Northglenn Heating & Air Conditioning, Inc..

  1. Both LED lights are off. This indicates your furnace might not be receiving power. Go to the breaker box to make sure the heater fuse is not flipped. Try resetting the fuse if it is in the “off” area. If it promptly trips after a subsequent reset, leave the breaker alone and call us at 303-452-4146.
  2. One light is stable and the other is blinking slowly. This signifies the flame rollout switch is likely not working right. The component is a critical safety tool that helps in avoiding fires and carbon monoxide. You shouldn’t seek to repair this problem yourself.
  3. An individual light is flashing rapidly and the other is blinking slowly. This often indicates power polarity has been reversed. Your heater may have a wiring error that needs professional help from Northglenn Heating & Air Conditioning, Inc..
  4. The pair of lights are blinking slowly. This indicates your furnace’s blower motor probably isn’t working. This piece distributes heated air from the heater into your space. We can aid in figuring out what’s wrong with this component.
  5. An individual light is flickering slowly and the other is flickering quickly. This means your heating system could have not enough voltage or a short circuit. Contact our technicians at 303-452-4146 for assistance.
  6. One light is blinking on, on and off while the other blinks on, off, on. This signifies there might be a fault with your furnace’s motherboard or wiring. Northglenn Heating & Air Conditioning, Inc. can pinpoint the issue and repair it.
  7. Both lights show alternate slow flickers. This means your HVAC system possibly has a flame issue. There may be a problem with its gas supply, gas valve or ignitor control. Get in touch with us at 303-452-4146 for support.
  8. A single light blinks slowly while the other is continuous. This often means your heater’s limit switch is experiencing an error. The switch stops your HVAC equipment from getting too hot. Contact the professionals at Northglenn Heating & Air Conditioning, Inc. for assistance.

Heater Blower Works But No Warm Air

Here’s what may be broken when you observe your furnace’s blower fan running, but you aren’t getting any heated air.

  • The pair of lights display every other quick blinks. This signifies your furnace ignitor might be broken. This piece ignites energy in your furnace to make warm air and should be fixed by a specialist from Northglenn Heating & Air Conditioning, Inc..

Trust Us for Skilled Furnace Repair

When you have to get your HVAC equipment fixed quickly, turn to the specialists at Northglenn Heating & Air Conditioning, Inc.. Our techs will fix the problem promptly and have your house feeling comfortable again soon. Call us at 303-452-4146 or contact us online to schedule an appointment today.

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