Furnace troubleshooting

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

While your Lennox® HVAC equipment can’t speak to 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.

Although there are some elementary HVAC adjustments you can finish on your own, many tasks are best taken care of by HVAC technicians. When your heater won’t kick on or deliver warm air, reach out to ACS Heating and Air Conditioning at 770-450-1539 for professional furnace repair in Tucker.

Our specialists will swiftly discover and repair the breakdown, even if you don’t use a Lennox heating system. We can repair whichever brands or models—and get the comfort reintroduced 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 engages this system to tell you it’s running correctly.

Regular function includes:

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

If you notice a solitary light going on and off slowly and the other blinking rapidly, your furnace may be having a low flame signal. This can occur even when your furnace is operating correctly. It indicates the flame sensing rod could be dirty or in the bad area on the burner. Contact us at 770-450-1539 for help.

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

Heater Will Not Turn On

Here are some of the light sequences you might observe when your heater will not 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 ensure the furnace fuse is not triggered. Attempt to reset the fuse if it has moved into the “off” area. If it promptly flips after you reset it, don’t try to reset it again and get in touch with us us at 770-450-1539.
  2. An individual light is stable and the other is flickering slowly. This shows the flame rollout switch is likely not working right. The part is a critical safety guard that helps in stopping fires and carbon monoxide. You shouldn’t try to repair this fault yourself.
  3. One light is flashing rapidly and the other is blinking slowly. This usually signifies power polarity has been transposed. Your heater could have a wiring error that calls for specialized help from ACS Heating and Air Conditioning.
  4. All lights are flickering slowly. This means your heating system’s blower motor possibly isn’t operating. This component sends heated 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 blinking quickly. This signifies your heater may have low voltage or a short circuit. Contact our professionals at 770-450-1539 for help.
  6. One light is flickering on, on and off while the other blinks on, off, on. This indicates there may be a problem with your heating system’s control board or wiring. ACS Heating and Air Conditioning can pinpoint the problem and take care of it.
  7. The pair of lights show alternate slow flickers. This indicates your heating system possibly has a flame problem. There may be an issue with its gas supply, gas valve or ignitor control. Call us at 770-450-1539 for support.
  8. A single light flashes slowly while the other is steady. This often means your heating system’s limit switch is not working. The switch keeps 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 at fault when you observe your furnace’s blower fan working, but you aren’t receiving any warmth.

  • The pair of lights are showing alternating rapid flickers. This indicates your furnace ignitor could not be working. This piece kindles fuel in your furnace to produce warm air and should be serviced by a specialist from ACS Heating and Air Conditioning.

Depend on Us for Professional Furnace Repair

When you need to have your HVAC equipment fixed fast, depend on the experts at ACS Heating and Air Conditioning. Our pros will take care of the problem promptly and have your rooms feeling relaxing again soon. Call us at 770-450-1539 or contact us online to schedule an appointment today.

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