Furnace troubleshooting

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

While your Lennox® heater can’t talk to you, it has a way to tell you about a furnace error.

Its motherboard has two LED lights that can display a fault code. Subject to the problem, your heating system might show continuous or flashing lights.

Though there are a few elementary furnace fixes you can take care of without an expert, the majority of fixes are best taken care of by HVAC technicians. When your heating system will not turn on or deliver heat, call Air-Right Energy Design, Inc. at 703-260-1148 for experienced furnace repair in Manassas.

Our experts will quickly pinpoint and take care of the malfunction, even if you don’t use a Lennox furnace. We can service whichever types or makes—and get the heat restored to your house fast.


What Does the Flickering Light on My Heater Mean?

Your heating system relies on lights to flash code when it isn’t working right. It also engages this system to tell you it’s operating like it should.

Normal operation includes:

  • Concurrent slow flash—furnace running properly.
  • Both lights flash fast—heater is starting to call for heat.

If you notice a single light going on and off slowly and the other flashing fast, your furnace may have a low flame signal. This can happen even when your furnace is working like it should. It means the flame sensing rod may be dirty or in the bad location on the burner. Call us at 703-260-1148 for help.

Here are some of the most common errors for Lennox heaters.

Heater Won’t Turn On

Here are many of the light patterns you might observe when your furnace refuses to or stay on. The majority of these problems have to be repaired by a professional, like one from Air-Right Energy Design, Inc..

  1. All LED lights are off. This signifies your HVAC system might not have power. Find the breaker box to confirm the heating system fuse hasn’t flipped. Try resetting the fuse if it has moved into the “off” area. If it instantly turns off after you reset it, leave the breaker alone and call us at 703-260-1148.
  2. A single light is stable and the other is flickering slowly. This signifies the flame rollout switch is possibly not working right. The part is an important safety mechanism that assists in preventing fires and carbon monoxide. You shouldn’t attempt to repair this issue on your own.
  3. One light is flashing fast and the other is flickering slowly. This often indicates power polarity has been reversed. Your heating system might have a wiring fault that calls for expert help from Air-Right Energy Design, Inc..
  4. The pair of lights are flickering slowly. This means your heater’s blower motor likely isn’t operating. This part distributes heated air from the heating system into your home. We can aid in pinpointing what’s wrong with this part.
  5. A single light is blinking slowly and the other is flickering rapidly. This signifies your heater might have not enough voltage or a short circuit. Call our technicians at 703-260-1148 for assistance.
  6. One light is blinking on, on and off while the other flashes on, off, on. This indicates there may be a problem with your heater’s motherboard or wiring. Air-Right Energy Design, Inc. can pinpoint the problem and take care of it.
  7. Both lights display alternating slow flashes. This indicates your HVAC equipment likely has a flame problem. There may be trouble with its gas supply, gas valve or ignitor control. Reach out to us at 703-260-1148 for support.
  8. An individual light blinks slowly while the other is continuous. This often means your heater’s limit switch is open. The switch prevents your heater from getting too hot. Get in touch with the specialists at Air-Right Energy Design, Inc. for help.

Heating System Blower Runs But No Heat

Here’s what may be at fault when you observe your heating equipment’s blower fan on, but you aren’t receiving any warmth.

  • The pair of lights are giving alternate fast flickers. This signifies your furnace ignitor might not be working. This part lights energy in your heater to create warmth and should be fixed by a technician from Air-Right Energy Design, Inc..

Depend on Us for Professional Furnace Repair

When you need to get your heating system in working order quickly, depend on the experts at Air-Right Energy Design, Inc.. Our pros will take care of the problem right away and have your rooms feeling relaxing again in a short time. Get in touch with us at 703-260-1148 or contact us online to schedule an appointment right away.

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