Furnace troubleshooting

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

While your Lennox® furnace can’t talk to you, it possesses a method to get your attention when there’s a furnace error.

Its control board has a set of LED lights that can share a fault code. Based on the problem, your heater might display solid or flashing lights.

While there are a few basic furnace fixes you can take care of on your own, many tasks are best left to HVAC technicians. When your heater refuses to turn on or give warm air, reach out to Bishop Heating & Air Conditioning at 760-784-9034 for expert furnace repair in Bishop.

Our experts will quickly detect and handle the breakdown, even if you don’t use a Lennox heater. We can service any types or configuration—and get the comfort restored to your home without delay.


What Does the Blinking Light on My Heating System Mean?

Your furnace uses lights to flash code when it isn’t working right. It also works these lights to tell you it’s heating properly.

Correct operation involves:

  • Simultaneous slow flash—furnace running properly.
  • Both lights flash fast—furnace is starting to call for heat.

If you notice a lone light going on and off slowly and the other blinking fast, your heater may have a low flame signal. This can occur even when your heating system is running properly. It means the flame sensing rod might be dirty or in the wrong spot on the burner. Reach out to us at 760-784-9034 for support.

Here are a few other of the most routine faults for Lennox heating systems.

Furnace Refuses to Start

Here are some of the light patterns you might notice when your heat will not or keep running. The majority of these issues must be taken care of by a professional, like one from Bishop Heating & Air Conditioning.

  1. Both LED lights are extinguished. This signifies your heater might not have power. Look at the breaker box to make sure the furnace fuse has not tripped. Try resetting the fuse if it’s in the “off” spot. If it rapidly trips after a subsequent reset, don’t try to reset it again and get in touch with us us at 760-784-9034.
  2. An individual light is stable and the other is flashing slowly. This means the flame rollout switch is possibly malfunctioning. The part is an essential safety tool that assists in preventing fires and carbon monoxide. You shouldn’t seek to take care of this issue without professional help.
  3. An individual light is flickering quickly and the other is blinking slowly. This often means power polarity has been inverted. Your furnace may have a wiring fault that calls for specialized support from Bishop Heating & Air Conditioning.
  4. All lights are flickering slowly. This indicates your furnace’s blower motor possibly isn’t operating. This component circulates hot air from the heater into your residence. We can aid in determining what’s wrong with this piece.
  5. A single light is flickering slowly and the other is blinking fast. This means your furnace might have insufficient voltage or a short circuit. Reach out to our technicians at 760-784-9034 for assistance.
  6. One light is flickering on, on and off while the other flickers on, off, on. This signifies there might be an issue with your furnace’s motherboard or wiring. Bishop Heating & Air Conditioning can pinpoint the issue and take care of it.
  7. Both lights show alternate slow blinks. This means your heater likely has a flame error. There may be trouble with its gas supply, gas valve or ignitor control. Contact us at 760-784-9034 for support.
  8. One light blinks slowly while the other stays continuous. This usually means your heating system’s limit switch is experiencing an error. The switch prevents your furnace from overheating. Reach out to the pros at Bishop Heating & Air Conditioning for help.

Heater Blower Works But No Heat

Here’s what might be broken when you hear your heating system’s blower fan working, but you aren’t receiving any heat.

  • The duo of lights display alternating rapid flickers. This signifies your furnace ignitor may not be in working order. This piece kindles gas in your HVAC equipment to create warmth and should be repaired by a technician from Bishop Heating & Air Conditioning.

Depend on Us for Professional Furnace Repair

When you have to get your heater in working order quickly, trust the professionals at Bishop Heating & Air Conditioning. Our technicians will take care of the issue without delay and have your rooms feeling relaxing again in no time. Reach out to us at 760-784-9034 or contact us online to get an appointment today.

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