Furnace troubleshooting

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

While your Lennox® furnace isn’t able to talk to you, it does have a method to tell you about a furnace error.

Its control board has a set of LED lights that can share a fault code. Subject to the malfunction, your heater may use solid or flashing lights.

Although there are some simple furnace fixes you can finish on your own, most services are best taken care of by experts. When your heating system won’t turn on or provide warmth, reach out to Morgner Inc. Air Conditioning & Heating at 314-262-4541 for experienced furnace repair in St. Louis.

Our specialists will speedily determine and take care of the issue, even if you don’t own a Lennox furnace. We can fix whichever kinds or makes—and get the warmth restored to your residence fast.


What Does the Blinking Light on My Heating System Mean?

Your furnace depends on lights to flash code when it is malfunctioning. It also engages this system to let you know it’s operating like it should.

Correct function includes:

  • Simultaneous slow flash—heater working properly.
  • Both lights flash fast—furnace is starting to call for heat.

If you see a solitary light blinking slowly and the other blinking fast, your furnace might be having a low flame signal. This can take place even when your furnace is working properly. It signifies the flame sensing rod could have build-up or in the incorrect spot on the burner. Reach out to us at 314-262-4541 for help.

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

Furnace Refuses to Start

Here are a few of the light patterns you may see when your heater refuses to or keep heating. The majority of these problems must be repaired by a professional, for instance from Morgner Inc. Air Conditioning & Heating.

  1. The pair of LED lights are off. This indicates your HVAC system might not have electricity. Examine the breaker box to ensure the heating system fuse has not tripped. Attempt to reset the fuse if it’s in the “off” spot. If it promptly trips after you reset it, don’t touch the breaker and call us at 314-262-4541.
  2. A single light is stable and the other is flickering slowly. This signifies the flame rollout switch is probably malfunctioning. The switch is an important safety tool that helps in avoiding fires and carbon monoxide. You shouldn’t try to handle this problem without professional help.
  3. A single light is blinking quickly and the other is flickering slowly. This usually signifies power polarity has been reversed. Your heater might have a wiring problem that calls for professional support from Morgner Inc. Air Conditioning & Heating.
  4. All lights are flashing slowly. This means your heating system’s blower motor likely isn’t working. This part moves warm air from the heater into your space. We can help in figuring out what’s causing a problem with this part.
  5. One light is flickering slowly and the other is flickering fast. This indicates your HVAC system could have not enough voltage or a short circuit. Get in touch with our technicians at 314-262-4541 for support.
  6. One light is flashing on, on and off while the other blinks on, off, on. This indicates there may be a malfunction with your heater’s control board or wiring. Morgner Inc. Air Conditioning & Heating can determine the issue and take care of it.
  7. Both lights are using alternate slow flashes. This signifies your HVAC system may have a flame problem. There could be trouble with its gas supply, gas valve or ignitor control. Contact us at 314-262-4541 for help.
  8. A single light flashes slowly while the other is steady. This often indicates your heating system’s limit switch is not working. The switch keeps your heating system from becoming too warm. Contact the experts at Morgner Inc. Air Conditioning & Heating for help.

Heating System Blower Operates But No Heat

Here’s what might be wrong when you hear your furnace’s blower fan working, but you aren’t receiving any heated air.

  • The pair of lights are showing every other rapid flickers. This means your furnace ignitor could not be working. This piece kindles fuel in your heater to produce warmth and should be serviced by an expert from Morgner Inc. Air Conditioning & Heating.

Trust Us for Professional Furnace Repair

When you need to get your furnace in working order without delay, turn to the experts at Morgner Inc. Air Conditioning & Heating. Our pros will handle the error promptly and have your rooms feeling cozy again in a short time. Get in touch with us at 314-262-4541 or contact us online to schedule an appointment today.

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