Furnace troubleshooting

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

While your Lennox® HVAC equipment isn’t able to speak to you, it has a method to tell you about a furnace error.

Its control board has double LED lights that can display a fault code. Depending on the malfunction, your furnace might use solid or flashing lights.

Though there are a few simple HVAC fixes you can complete without an expert, the majority of tasks are best handled by the professionals. When your heating system refuses to start or give heated air, call McFadden Heating & Cooling at 1-866-781-0111 for expert furnace repair in Dresden.

Our technicians will quickly identify and handle the problem, even if you don’t own a Lennox heater. We can service whichever brands or configuration—and get the warmth reintroduced to your house quickly.


What Does the Blinking 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 relay it’s operating properly.

Regular heating consists of:

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

If you notice a lone light going on and off slowly and the other going on and off rapidly, your furnace might be experiencing a low flame signal. This can happen even when your heater is heating properly. It means the flame sensing rod may have build-up or in the incorrect spot on the burner. Reach out to us at 1-866-781-0111 for help.

Here are a few other of the most typical faults for Lennox heaters.

Heating System Refuses to Turn On

Here are a few of the light arrangements you may see when your heat will not or keep operating. The majority of these problems need to be fixed by a technician, like one from McFadden Heating & Cooling.

  1. The pair of LED lights aren’t lit. This means your heating system might not have power. Go to the breaker box to ensure the furnace fuse isn’t triggered. Try resetting the fuse if it has moved into the “off” area. If it instantly trips after you reset it, leave the breaker alone and call us at 1-866-781-0111.
  2. An individual light is unchanging and the other is blinking slowly. This shows the flame rollout switch is may be not working right. The part is an important safety device that helps in avoiding fires and carbon monoxide. You shouldn’t attempt to handle this issue without professional help.
  3. An individual light is flickering quickly and the other is flashing slowly. This likely indicates power polarity has been transposed. Your heater might have a wiring issue that calls for professional aid from McFadden Heating & Cooling.
  4. The duo of lights are flickering slowly. This means your heating system’s blower motor probably isn’t working. This piece distributes heated air from the furnace into your residence. We can help in pinpointing what’s causing a problem with this part.
  5. An individual light is flickering slowly and the other is flashing fast. This signifies your furnace may have not enough voltage or a short circuit. Reach out to our professionals at 1-866-781-0111 for help.
  6. One light is flashing on, on and off while the other blinks on, off, on. This means there might be an error with your heater’s control panel or wiring. McFadden Heating & Cooling can find the issue and take care of it.
  7. Both lights are using alternating slow flickers. This signifies your heater possibly has a flame problem. There might be a problem with its gas supply, gas valve or ignitor control. Call us at 1-866-781-0111 for assistance.
  8. A single light flickers slowly while the other remains solid. This typically signifies your furnace’s limit switch is not working. The switch prevents your HVAC equipment from becoming too warm. Reach out to the pros at McFadden Heating & Cooling for assistance.

Heater Blower Runs But No Warm Air

Here’s what may be wrong when you hear your heating system’s blower fan running, but you aren’t gaining any heat.

  • The pair of lights display every other quick flickers. This signifies your furnace ignitor may not be working. This component kindles fuel in your HVAC equipment to make warmth and should be repaired by a professional from McFadden Heating & Cooling.

Depend on Us for Skilled Furnace Repair

When you have to get your heating system repaired without delay, depend on the technicians at McFadden Heating & Cooling. Our technicians will fix the error promptly and have your residence feeling relaxing again in a short time. Contact us at 1-866-781-0111 or contact us online to schedule an appointment right away.

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