Furnace troubleshooting

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

While your Lennox® heater can’t chat with you, it has a method to get your attention when there’s a furnace error.

Its control board has double LED lights that can show a fault code. Based on the problem, your heater might show solid or flashing lights.

Although there are certain simple furnace fixes you can take care of yourself, many repairs are best handled by the professionals. When your heating system won’t turn on or provide heated air, reach out to Air Houston Mechanical LLC at 832-777-1521 for expert furnace repair in Huffman.

Our experts will quickly diagnose and handle the issue, even if you don’t use a Lennox heater. We can service any kinds or models—and get the heat reintroduced to your house without delay.


What Does the Flashing Light on My Heater Mean?

Your furnace depends on lights to flash code when it needs to be repaired. It also uses these lights to relay it’s running correctly.

Normal operation consists of:

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

If you notice one light blinking slowly and the other going on and off quickly, your heater might have a low flame signal. This can take place even when your heater is operating properly. It signifies the flame sensing rod could need to be cleaned or in the incorrect location on the burner. Contact us at 832-777-1521 for assistance.

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

Furnace Will Not Kick On

Here are some of the light sequences you could see when your heating system refuses to or keep heating. Most of these problems must be handled by a technician, for instance from Air Houston Mechanical LLC.

  1. The pair of LED lights aren’t lit. This signifies your heating system might not have electricity. Go to the breaker box to confirm the heating system fuse isn’t flipped. You should reset the fuse if it’s in the “off” area. If it promptly turns off after a subsequent reset, don’t try to reset it again and contact us at 832-777-1521.
  2. One light is continuous and the other is blinking slowly. This means the flame rollout switch is likely open. The switch is an essential safety tool that assists in preventing fires and carbon monoxide. You shouldn’t try to take care of this problem on your own.
  3. A single light is flickering fast and the other is flashing slowly. This typically indicates power polarity has been inverted. Your furnace might have a wiring error that calls for professional aid from Air Houston Mechanical LLC.
  4. The duo of lights are flickering slowly. This means your heater’s blower motor possibly isn’t operating. This piece sends warm air from the HVAC system into your rooms. We can aid in figuring out what’s wrong with this piece.
  5. An individual light is flickering slowly and the other is flickering rapidly. This means your HVAC system might have not enough voltage or a short circuit. Call our technicians at 832-777-1521 for assistance.
  6. One light is flashing on, on and off while the other blinks on, off, on. This signifies there might be a problem with your HVAC system’s control panel or wiring. Air Houston Mechanical LLC can find the fault and repair it.
  7. The duo of lights show every other slow blinks. This signifies your furnace may have a flame error. There might be an issue with its gas supply, gas valve or ignitor control. Contact us at 832-777-1521 for assistance.
  8. One light flashes slowly while the other stays steady. This typically signifies your furnace’s limit switch is experiencing an error. The switch keeps your heater from overheating. Reach out to the professionals at Air Houston Mechanical LLC for assistance.

Heater Blower Operates But No Warm Air

Here’s what may be broken when you hear your heater’s blower fan working, but you aren’t getting any warmth.

  • The duo of lights are showing alternating quick flashes. This signifies your furnace ignitor may not be working. This piece kindles energy in your heating system to create warm air and should be serviced by an expert from Air Houston Mechanical LLC.

Trust Us for Professional Furnace Repair

When you have to have your HVAC equipment in working order quickly, depend on the specialists at Air Houston Mechanical LLC. Our technicians will fix the error quickly and have your rooms feeling relaxing again soon. Contact us at 832-777-1521 or contact us online to schedule an appointment today.

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