Furnace troubleshooting

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

While your Lennox® heater cannot speak to you, it has a way to communicate a furnace error.

Its motherboard has twin LED lights that can display a fault code. Subject to the fault, your heating system could use solid or flashing lights.

Though there are certain basic furnace fixes you can take care of on your own, most services are best handled by experts. When your heating system won’t start or give heated air, get in touch with Stanford Heating & Cooling at 812-825-8695 for professional furnace repair in Bloomfield.

Our technicians will rapidly detect and fix the issue, even if you don’t have a Lennox heating system. We can fix whichever kinds or models—and get the heat reintroduced to your home without delay.


What Does the Blinking Light on My Heater Mean?

Your heater uses lights to flash code when it requires repairs. It also uses this system to relay it’s heating properly.

Normal function involves:

  • Concurrent slow flash—heating system heating correctly.
  • Concurrent fast flash—furnace is starting to call for heat.

If you realize that a solitary light flashing slowly and the other flashing rapidly, your heater could be having a low flame signal. This can occur even when your furnace is working correctly. It means the flame sensing rod may be dirty or in the incorrect location on the burner. Contact us at 812-825-8695 for assistance.

Here are several other of the most common problems for Lennox furnaces.

Furnace Won’t Turn On

Here are many of the light arrangements you may see when your heat refuses to or keep operating. The majority of these issues must be taken care of by a specialist, such as one from Stanford Heating & Cooling.

  1. All LED lights are extinguished. This signifies your heating system might not have power. Check the breaker box to ensure the furnace fuse hasn’t triggered. Try resetting the fuse if it is in the “off” area. If it promptly trips following a reset, don’t try to reset it again and call us at 812-825-8695.
  2. One light is stable and the other is flickering slowly. This implies the flame rollout switch is likely not working right. The switch is an important safety mechanism that aids in preventing fires and carbon monoxide. You shouldn’t attempt to handle this malfunction without professional help.
  3. One light is flickering quickly and the other is flickering slowly. This often indicates power polarity has been inverted. Your heating system may have a wiring error that requires specialized support from Stanford Heating & Cooling.
  4. Both lights are flashing slowly. This means your heating system’s blower motor likely isn’t operating. This component sends warm air from the HVAC system into your residence. We can assist in pinpointing what’s wrong with this component.
  5. A single light is flickering slowly and the other is blinking rapidly. This indicates your heating system could have not enough voltage or a short circuit. Reach out to our experts at 812-825-8695 for help.
  6. One light is flashing on, on and off while the other blinks on, off, on. This signifies there could be trouble with your heater’s control board or wiring. Stanford Heating & Cooling can find the error and take care of it.
  7. Both lights show alternate slow blinks. This signifies your heater may have a flame error. There may be an issue with its gas supply, gas valve or ignitor control. Contact us at 812-825-8695 for assistance.
  8. A single light blinks slowly while the other remains continuous. This typically means your heating system’s limit switch is open. The switch stops your furnace from getting too hot. Call the professionals at Stanford Heating & Cooling for support.

Heating System 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.

  • Both lights display alternating fast flashes. This indicates your furnace ignitor might not be in working order. This component lights fuel in your HVAC equipment to create warmth and should be fixed by a professional from Stanford Heating & Cooling.

Turn to Us for Expert Furnace Repair

When you have to get your heater repaired without delay, trust the specialists at Stanford Heating & Cooling. Our pros will handle the problem right away and have your rooms feeling cozy again in a short time. Reach out to us at 812-825-8695 or contact us online to request an appointment right away.

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