Furnace troubleshooting

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

While your Lennox® heating system isn’t able to talk to you, it has a procedure to communicate a furnace error.

Its control panel has double LED lights that can display a fault code. Based on the failure, your furnace may use steady or flashing lights.

While there are a few simple HVAC repairs you can complete without an expert, the majority of services are best handled by HVAC technicians. When your heating system will not start or give heat, call Northern Comfort Inc at 507-387-6596 for professional furnace repair in Mankato area.

Our specialists will speedily discover and repair the breakdown, even if you don’t use a Lennox heater. We can repair whichever types or configuration—and get the heat returned to your home without delay.


What Does the Flashing Light on My Furnace Mean?

Your heater depends on lights to flash code when it needs to be repaired. It also works this setup to tell you it’s heating correctly.

Normal operation involves:

  • Concurrent slow flash—heater operating like it should.
  • Simultaneous fast flash—heater is starting to call for heat.

If you notice one light flashing slowly and the other blinking rapidly, your furnace could be experiencing a low flame signal. This can take place even when your furnace is working correctly. It means the flame sensing rod could have build-up or in the wrong area on the burner. Contact us at 507-387-6596 for assistance.

Here are some of the most common issues for Lennox heaters.

Furnace Will Not Start

Here are a few of the light arrangements you may observe when your heat won’t turn on or keep operating. The majority of these issues need to be taken care of by a professional, such as one from Northern Comfort Inc.

  1. Both LED lights are off. This signifies your heater might not have electricity. Go to the breaker box to ensure the heater fuse hasn’t tripped. You should reset the fuse if it has moved into the “off” position. If it promptly flips after you reset it, don’t try to reset it again and get in touch with us us at 507-387-6596.
  2. One light is solid and the other is flashing slowly. This shows the flame rollout switch is possibly open. The part is a critical safety guard that helps in avoiding fires and carbon monoxide. You shouldn’t seek to handle this malfunction yourself.
  3. An individual light is flashing quickly and the other is flickering slowly. This typically indicates power polarity has been transposed. Your heater might have a wiring fault that calls for expert support from Northern Comfort Inc.
  4. The pair of lights are flashing slowly. This indicates your heater’s blower motor likely isn’t running. This piece circulates heated air from the heater into your house. We can assist in pinpointing what’s causing a problem with this component.
  5. An individual light is flashing slowly and the other is flashing fast. This indicates your heating system could have not enough voltage or a short circuit. Reach out to our professionals at 507-387-6596 for assistance.
  6. One light is blinking on, on and off while the other flickers on, off, on. This means there may be an issue with your heater’s motherboard or wiring. Northern Comfort Inc can find the issue and fix it.
  7. The pair of lights show alternating slow flickers. This means your heater possibly has a flame problem. There could be a problem with its gas supply, gas valve or ignitor control. Get in touch with us at 507-387-6596 for help.
  8. An individual light flashes slowly while the other stays steady. This typically means your furnace’s limit switch is malfunctioning. The switch prevents your heating system from overheating. Contact the specialists at Northern Comfort Inc for assistance.

Heater Blower Runs But No Warm Air

Here’s what may be broken when you notice your heater’s blower fan on, but you aren’t gaining any warm air.

  • The pair of lights display alternating quick flashes. This means your furnace ignitor may not be in working order. This piece lights fuel in your heating system to create warmth and should be serviced by a professional from Northern Comfort Inc.

Turn to Us for Skilled Furnace Repair

When you have to have your furnace in working order fast, depend on the technicians at Northern Comfort Inc. Our technicians will handle the issue right away and have your rooms feeling relaxing again in no time. Call us at 507-387-6596 or contact us online to get an appointment now.

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