Furnace troubleshooting

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

While your Lennox® heating system can’t talk to you, it does have a procedure to communicate a furnace error.

Its motherboard has double LED lights that can display a fault code. Based on the malfunction, your heating system might show continuous or flashing lights.

Although there are certain elementary heating fixes you can finish without an expert, the majority of services are best handled by the professionals. When your heater won’t kick on or provide heat, get in touch with MPC Heating & Cooling at 308-832-4321 for experienced furnace repair in Chadron.

Our specialists will rapidly spot and repair the issue, even if you don’t have a Lennox heater. We can fix whichever kinds or makes—and get the warmth returned to your residence without delay.


What Does the Flashing Light on My Heater Mean?

Your heater uses lights to flash code when it isn’t working right. It also engages this system to let you know it’s working properly.

Normal function includes:

  • Both lights flash slowly—furnace running correctly.
  • Concurrent fast flash—heater is initiating the call for heat.

If you realize that one light flashing slowly and the other flashing rapidly, your heater might be having a low flame signal. This can occur even when your heating system is running properly. It means the flame sensing rod might have build-up or in the wrong area on the burner. Contact us at 308-832-4321 for help.

Here are some of the most routine errors for Lennox heaters.

Furnace Won’t Kick On

Here are many of the light sequences you could see when your heating system will not or stay on. Most of these issues must be handled by an expert, such as one from MPC Heating & Cooling.

  1. The pair of LED lights are extinguished. This means your heater might not have power. Go to the breaker box to ensure the heater fuse has not triggered. Try resetting the fuse if it is in the “off” area. If it rapidly flips after you reset it, don’t touch the breaker and contact us at 308-832-4321.
  2. A single light is continuous and the other is blinking slowly. This shows the flame rollout switch is likely malfunctioning. The part is an important safety guard that helps in preventing fires and carbon monoxide. You shouldn’t try to repair this malfunction yourself.
  3. An individual light is flashing fast and the other is flashing slowly. This often means power polarity has been inverted. Your furnace may have a wiring fault that calls for professional help from MPC Heating & Cooling.
  4. Both lights are flashing slowly. This indicates your furnace’s blower motor probably isn’t running. This piece circulates hot air from the furnace into your house. We can help in figuring out what’s causing a problem with this component.
  5. An individual light is blinking slowly and the other is flashing fast. This means your heating system might have low voltage or a short circuit. Call our professionals at 308-832-4321 for assistance.
  6. One light is flickering on, on and off while the other flashes on, off, on. This signifies there may be a malfunction with your furnace’s control panel or wiring. MPC Heating & Cooling can determine the fault and handle it.
  7. The pair of lights show alternate slow flashes. This means your heating system possibly has a flame failure. There may be an issue with its gas supply, gas valve or ignitor control. Contact us at 308-832-4321 for assistance.
  8. One light flashes slowly while the other remains continuous. This typically signifies your furnace’s limit switch is malfunctioning. The switch prevents your furnace from becoming too warm. Contact the professionals at MPC Heating & Cooling for support.

Furnace Blower Works But No Warm Air

Here’s what may be at fault when you observe your heater’s blower fan running, but you aren’t receiving any heat.

  • The pair of lights are giving alternate fast flashes. This signifies your furnace ignitor might not be working. This part lights fuel in your heater to produce heat and should be fixed by an expert from MPC Heating & Cooling.

Turn to Us for Professional Furnace Repair

When you have to have your furnace fixed without delay, depend on the specialists at MPC Heating & Cooling. Our technicians will handle the error quickly and have your rooms feeling relaxing again in no time. Reach out to us at 308-832-4321 or contact us online to get an appointment today.

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