Furnace troubleshooting

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

While your Lennox® heater isn’t able to chat with you, it has a procedure to communicate a furnace error.

Its control panel has twin LED lights that can share a fault code. Based on the malfunction, your furnace may use solid or flashing lights.

Though there are certain elementary HVAC repairs you can take care of on your own, most repairs are best left to experts. When your furnace refuses to start or put out warmth, reach out to Southern Heating & Cooling Inc. at 256-574-1300 for professional furnace repair in Scottsboro.

Our experts will swiftly identify and take care of the failure, even if you don’t own a Lennox heater. We can service all brands or models—and get the heat reintroduced to your home quickly.


What Does the Flashing Light on My Furnace Mean?

Your furnace relies on lights to flash code when it isn’t working right. It also uses this system to tell you it’s heating like it should.

Regular function includes:

  • Simultaneous slow flash—heater operating like it should.
  • Simultaneous fast flash—heating system is beginning to call for heat.

If you notice a single light flashing 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 working correctly. It indicates the flame sensing rod may need to be cleaned or in the bad spot on the burner. Contact us at 256-574-1300 for assistance.

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

Heating System Won’t Turn On

Here are some of the light arrangements you may observe when your heater will not or stay on. The bulk of these problems must be repaired by a professional, such as one from Southern Heating & Cooling Inc..

  1. All LED lights aren’t lit. This signifies your heating system might not have power. Check the breaker box to ensure the furnace fuse has not triggered. Try resetting the fuse if it is in the “off” position. If it rapidly turns off following a reset, don’t try to reset it again and call us at 256-574-1300.
  2. A single light is continuous and the other is flashing slowly. This signifies the flame rollout switch is likely malfunctioning. The switch is an essential safety guard that assists in stopping fires and carbon monoxide. You shouldn’t seek to repair this problem without professional help.
  3. An individual light is flickering quickly and the other is flickering slowly. This typically signifies power polarity has been inverted. Your heater may have a wiring error that calls for expert support from Southern Heating & Cooling Inc..
  4. The duo of lights are flashing slowly. This signifies your heater’s blower motor likely isn’t working. This part circulates hot air from the heater into your house. We can assist in determining what’s causing an issue with this part.
  5. An individual light is blinking slowly and the other is blinking fast. This means your HVAC system could have low voltage or a short circuit. Reach out to our specialists at 256-574-1300 for support.
  6. One light is flashing on, on and off while the other flashes on, off, on. This indicates there may be an error with your heating system’s motherboard or wiring. Southern Heating & Cooling Inc. can find the issue and take care of it.
  7. The pair of lights show alternate slow flickers. This indicates your HVAC system likely has a flame issue. There might be a problem with its gas supply, gas valve or ignitor control. Contact us at 256-574-1300 for assistance.
  8. A single light flickers slowly while the other remains solid. This often means your HVAC equipment’s limit switch is not working. The switch prevents your heating system from becoming too warm. Contact the professionals at Southern Heating & Cooling Inc. for help.

Furnace Blower Operates But No Warm Air

Here’s what might be wrong when you observe your heater’s blower fan on, but you aren’t gaining any heat.

  • The pair of lights are showing alternate quick flickers. This means your furnace ignitor might not be in working order. This part kindles gas in your HVAC equipment to make warm air and should be fixed by a technician from Southern Heating & Cooling Inc..

Turn to Us for Professional Furnace Repair

When you have to get your furnace in working order without delay, turn to the professionals at Southern Heating & Cooling Inc.. Our pros will handle the error right away and have your home feeling cozy again soon. Get in touch with us at 256-574-1300 or contact us online to request an appointment now.

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