Furnace troubleshooting

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

While your Lennox® heater can’t chat with you, it does have a method to communicate a furnace error.

Its control panel has a set of LED lights that can display a fault code. Subject to the fault, your furnace may display continuous or flashing lights.

Though there are various elementary heating adjustments you can finish without an expert, many services are best taken care of by HVAC technicians. When your heating system won’t start or deliver warm air, call ACS Heating and Air Conditioning at 770-450-1539 for professional furnace repair in Tucker.

Our specialists will swiftly identify and repair the breakdown, even if you don’t use a Lennox heater. We can service whichever brands or makes—and get the comfort returned to your house fast.


What Does the Flashing Light on My Furnace Mean?

Your heater uses lights to flash code when it is malfunctioning. It also uses this system to tell you it’s running like it should.

Regular heating involves:

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

If you realize that a solitary light blinking slowly and the other blinking fast, your furnace may be having a low flame signal. This can take place even when your furnace is working correctly. It signifies the flame sensing rod could be dirty or in the bad location on the burner. Reach out to us at 770-450-1539 for assistance.

Here are several other of the most typical errors for Lennox HVAC systems.

Heater Will Not Turn On

Here are some of the light patterns you could notice when your heat refuses to or keep operating. Most of these errors have to be repaired by a technician, for instance from ACS Heating and Air Conditioning.

  1. Both LED lights are off. This signifies your heating system might not be receiving power. Check the breaker box to confirm the furnace fuse is not flipped. Try resetting the fuse if it has moved into the “off” spot. If it immediately flips after you reset it, don’t touch the breaker and contact us at 770-450-1539.
  2. A single light is stable and the other is blinking slowly. This shows the flame rollout switch is likely not working right. The component is a critical safety guard that helps in stopping fires and carbon monoxide. You shouldn’t attempt to repair this fault yourself.
  3. One light is flashing rapidly and the other is flickering slowly. This typically indicates power polarity has been inverted. Your heater could have a wiring error that calls for specialized help from ACS Heating and Air Conditioning.
  4. All lights are blinking slowly. This means your heating system’s blower motor possibly isn’t operating. This component sends hot air from the furnace into your home. We can help in pinpointing what’s causing a problem with this piece.
  5. A single light is blinking slowly and the other is flickering quickly. This signifies your heater may have low voltage or a short circuit. Contact our experts at 770-450-1539 for help.
  6. One light is blinking on, on and off while the other flickers on, off, on. This indicates there may be an issue with your heating system’s control board or wiring. ACS Heating and Air Conditioning can find the problem and repair it.
  7. The duo of lights show alternate slow flickers. This indicates your heating system possibly has a flame problem. There might be an issue with its gas supply, gas valve or ignitor control. Call us at 770-450-1539 for support.
  8. An individual light flashes slowly while the other is solid. This typically means your heating system’s limit switch is not working. The switch stops your HVAC equipment from becoming too warm. Call the specialists at ACS Heating and Air Conditioning for support.

Heating System Blower Works But No Warmth

Here’s what could be broken when you observe your heating system’s blower fan working, but you aren’t getting any warmth.

  • The duo of lights are showing alternating rapid flickers. This signifies your furnace ignitor might be broken. This component kindles gas in your furnace to produce warmth and should be serviced by a specialist from ACS Heating and Air Conditioning.

Depend on Us for Professional Furnace Repair

When you need to get your HVAC equipment fixed without delay, trust the experts at ACS Heating and Air Conditioning. Our pros will fix the error promptly and have your home feeling cozy again soon. Reach out to us at 770-450-1539 or contact us online to schedule an appointment today.

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