Furnace troubleshooting

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

While your Lennox® heater can’t speak to you, it possesses a way to get your attention when there’s a furnace error.

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

Though there are a few simple HVAC repairs you can complete on your own, many services are best taken care of by the professionals. When your heating system refuses to kick on or deliver warm air, reach out to Rescue Heating & Air at 361-265-4371 for professional furnace repair in Alice.

Our experts will quickly detect and fix the malfunction, even if you don’t use a Lennox furnace. We can repair all kinds or models—and get the warmth reintroduced to your home without delay.


What Does the Flashing Light on My Heating System Mean?

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

Correct function involves:

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

If you notice a lone light flashing slowly and the other going on and off quickly, your heater may have a low flame signal. This can happen even when your furnace is operating properly. It signifies the flame sensing rod may need to be cleaned or in the wrong spot on the burner. Call us at 361-265-4371 for help.

Here are several other of the most routine faults for Lennox heating systems.

Heater Refuses to Kick On

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

  1. All 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” area. If it promptly turns off after a subsequent reset, don’t try to reset it again and call us at 361-265-4371.
  2. A single light is stable and the other is flickering slowly. This means the flame rollout switch is likely open. The component is an important safety mechanism that aids in avoiding fires and carbon monoxide. You shouldn’t seek to handle this malfunction without professional help.
  3. An individual light is flashing fast and the other is blinking slowly. This typically means power polarity has been transposed. Your heater 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 running. This component distributes warm air from the HVAC system into your residence. We can assist in determining what’s causing a problem with this piece.
  5. A single light is blinking slowly and the other is blinking rapidly. This signifies your heating system could have insufficient voltage or a short circuit. Call our experts at 361-265-4371 for help.
  6. One light is flashing on, on and off while the other flickers on, off, on. This indicates there may be trouble 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 display alternating slow blinks. This means your HVAC system possibly 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. A single light flashes slowly while the other stays solid. This typically indicates your HVAC equipment’s limit switch is not working. The switch prevents your furnace from becoming too warm. Contact the professionals at Rescue Heating & Air for support.

Heating System Blower Runs But No Warmth

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 pair of lights display alternating quick flashes. This indicates your furnace ignitor might not be in working order. This piece ignites energy in your furnace to produce warmth and should be serviced by a professional from Rescue Heating & Air .

Trust Us for Professional Furnace Repair

When you have to have your heating system fixed without delay, turn to the professionals at Rescue Heating & Air . Our techs will fix the fault without delay and have your home feeling cozy 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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