Furnace troubleshooting

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

While your Lennox® heater can’t chat with you, it has a way to communicate a furnace error.

Its control board has twin LED lights that can show a fault code. Depending on the fault, your heating system may display continuous or flashing lights.

Although there are a few basic heating repairs you can complete without an expert, many tasks are best taken care of by the professionals. When your heater refuses to start or deliver warm air, reach out to Rescue Heating & Air at 361-265-4371 for professional furnace repair in Alice.

Our specialists will quickly detect and fix the malfunction, even if you don’t use a Lennox furnace. We can service all kinds or makes—and get the comfort returned to your home quickly.


What Does the Flickering Light on My Heating System Mean?

Your furnace uses lights to flash code when it requires repairs. It also uses this system to let you know it’s heating like it should.

Regular heating involves:

  • Both lights flash slowly—heating system operating properly.
  • Concurrent fast flash—heating system is starting to call for heat.

If you notice a lone light flashing slowly and the other blinking quickly, your heating system may be experiencing a low flame signal. This can happen even when your furnace is operating properly. It indicates the flame sensing rod could need to be cleaned or in the incorrect spot on the burner. Call us at 361-265-4371 for help.

Here are several other of the most typical faults for Lennox furnaces.

Heating System Refuses to Kick On

Here are many of the light sequences you could notice when your heater will not or keep operating. Most of these errors must be fixed by a professional, such as one from Rescue Heating & Air .

  1. The duo of LED lights are off. This signifies your HVAC system might not have electricity. Check the breaker box to make sure the furnace fuse is not flipped. Try resetting the fuse if it’s in the “off” spot. If it promptly flips following a reset, don’t touch the breaker and call us at 361-265-4371.
  2. A single light is stable and the other is blinking slowly. This shows the flame rollout switch is probably open. The part is an important safety tool that assists in avoiding fires and carbon monoxide. You shouldn’t seek to handle this problem on your own.
  3. An individual light is flashing fast and the other is blinking slowly. This usually means power polarity has been inverted. Your heating system may have a wiring error that requires expert support from Rescue Heating & Air .
  4. The pair of lights are blinking slowly. This means your heater’s blower motor probably isn’t operating. This piece distributes warm air from the HVAC system into your house. We can aid in determining what’s causing an issue with this component.
  5. A single light is flickering slowly and the other is flickering fast. This signifies your heating system might have insufficient voltage or a short circuit. Reach out to our professionals at 361-265-4371 for help.
  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 HVAC system’s control board or wiring. Rescue Heating & Air can find the problem and take care of it.
  7. The duo of lights are using alternating slow blinks. This means your HVAC system likely has a flame problem. There might be a problem with its gas supply, gas valve or ignitor control. Contact us at 361-265-4371 for support.
  8. An individual light flashes slowly while the other remains solid. This often indicates your HVAC equipment’s limit switch is not working. The switch prevents your HVAC system from becoming too warm. Contact the experts at Rescue Heating & Air for support.

Heater Blower Runs But No Warm Air

Here’s what could be at fault when you observe your heater’s blower fan running, but you aren’t getting any heated air.

  • The duo of lights display alternating rapid flashes. This indicates your furnace ignitor could not be in working order. This piece ignites energy in your heating system to produce warmth and should be serviced by an expert from Rescue Heating & Air .

Trust Us for Skilled Furnace Repair

When you have to have your heating system fixed without delay, turn to the specialists at Rescue Heating & Air . Our techs will take care of the fault promptly and have your rooms feeling relaxing again in no time. Reach out to us at 361-265-4371 or contact us online to request an appointment right away.

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