Furnace troubleshooting

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

While your Lennox® furnace can’t chat with you, it has a method to communicate a furnace error.

Its control panel has double LED lights that can share a fault code. Based on the fault, your heater might show continuous or flashing lights.

Although there are certain basic furnace adjustments you can take care of on your own, the majority of repairs are best handled by the professionals. When your heating system won’t kick on or deliver heated air, get in touch with 1st Choice Heating & Air Conditioning, Inc. at 949-204-0859 for experienced furnace repair in Lake Forest.

Our experts will quickly pinpoint and handle the failure, even if you don’t have a Lennox heating system. We can fix any brands or makes—and get the heat returned to your residence without delay.


What Does the Flickering Light on My Furnace Mean?

Your furnace uses lights to flash code when it requires repairs. It also uses these lights to let you know it’s heating like it should.

Correct function includes:

  • Concurrent slow flash—heater heating properly.
  • Simultaneous fast flash—heater is beginning to call for heat.

If you realize that a solitary light going on and off slowly and the other going on and off quickly, your heater could have a low flame signal. This can happen even when your heater is heating properly. It signifies the flame sensing rod might be dirty or in the bad location on the burner. Reach out to us at 949-204-0859 for help.

Here are a few other of the most common issues for Lennox heating systems.

Heater Will Not Turn On

Here are some of the light patterns you might see when your furnace refuses to or stay on. Most of these errors need to be fixed by an expert, for instance from 1st Choice Heating & Air Conditioning, Inc..

  1. Both LED lights aren’t lit. This means your heater might not have power. Look at the breaker box to confirm the heater fuse is not tripped. Try resetting the fuse if it has moved into the “off” position. If it immediately turns off after a subsequent reset, leave the breaker alone and get in touch with us us at 949-204-0859.
  2. A single light is stable and the other is flashing slowly. This means the flame rollout switch is likely malfunctioning. The switch is a critical safety tool that assists in stopping fires and carbon monoxide. You shouldn’t seek to handle this issue on your own.
  3. A single light is flickering rapidly and the other is flashing slowly. This often signifies power polarity has been transposed. Your heating system may have a wiring error that calls for specialized help from 1st Choice Heating & Air Conditioning, Inc..
  4. Both lights are flickering slowly. This means your furnace’s blower motor probably isn’t operating. This component moves warm air from the heater into your home. We can help in figuring out what’s causing an issue with this component.
  5. An individual light is blinking slowly and the other is flickering quickly. This signifies your HVAC system may have low voltage or a short circuit. Reach out to our technicians at 949-204-0859 for assistance.
  6. One light is blinking on, on and off while the other flashes on, off, on. This indicates there may be an error with your heater’s control board or wiring. 1st Choice Heating & Air Conditioning, Inc. can pinpoint the error and fix it.
  7. Both lights display alternate slow blinks. This signifies your furnace likely has a flame failure. There might be an issue with its gas supply, gas valve or ignitor control. Call us at 949-204-0859 for support.
  8. A single light flickers slowly while the other remains steady. This often signifies your heater’s limit switch is open. The switch keeps your HVAC equipment from overheating. Contact the professionals at 1st Choice Heating & Air Conditioning, Inc. for support.

Furnace Blower Runs But No Warmth

Here’s what may be broken when you hear your furnace’s blower fan on, but you aren’t receiving any warmth.

  • The pair of lights are giving alternating fast flashes. This means your furnace ignitor might be broken. This component lights fuel in your HVAC equipment to make heat and should be serviced by a technician from 1st Choice Heating & Air Conditioning, Inc..

Trust Us for Skilled Furnace Repair

When you have to have your furnace fixed quickly, turn to the professionals at 1st Choice Heating & Air Conditioning, Inc.. Our techs will fix the issue quickly and have your space feeling comfortable again in no time. Reach out to us at 949-204-0859 or contact us online to request an appointment today.

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