Furnace troubleshooting

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

While your Lennox® HVAC equipment can’t talk to you, it possesses a way to tell you about a furnace error.

Its motherboard has two LED lights that can display a fault code. Based on the problem, your heating system could display continuous or flashing lights.

Though there are a few elementary furnace fixes you can take care of on your own, most fixes are best taken care of by HVAC technicians. When your heater refuses to turn on or deliver heat, reach out to Air-Right Energy Design, Inc. at 703-260-1148 for expert furnace repair in Manassas.

Our experts will speedily diagnose and take care of the malfunction, even if you don’t own a Lennox furnace. We can service all kinds or makes—and get the heat restored to your house fast.


What Does the Flickering Light on My Heater Mean?

Your heating system depends on lights to flash code when it isn’t working right. It also engages this system to tell you it’s running correctly.

Normal operation includes:

  • Simultaneous slow flash—heater running properly.
  • Simultaneous fast flash—heater is starting to call for heat.

If you notice a single light blinking slowly and the other flashing rapidly, your furnace may be experiencing a low flame signal. This can happen even when your furnace is operating like it should. It means the flame sensing rod may be dirty or in the bad area on the burner. Call us at 703-260-1148 for assistance.

Here are several other of the most common errors for Lennox heaters.

Heater Won’t Turn On

Here are many of the light patterns you could observe when your furnace refuses to or keep heating. The majority of these problems have to be repaired by an expert, 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 ensure the heating system fuse isn’t flipped. Attempt to reset 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. An individual light is stable and the other is flickering slowly. This signifies the flame rollout switch is possibly malfunctioning. The part is an important safety mechanism that aids in preventing fires and carbon monoxide. You shouldn’t try to repair this issue without professional help.
  3. One light is flashing rapidly and the other is flickering slowly. This often indicates power polarity has been reversed. Your heater could have a wiring fault that calls for expert support from Air-Right Energy Design, Inc..
  4. Both lights are flickering slowly. This means your heater’s blower motor possibly 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 indicates your heater might have insufficient voltage or a short circuit. Call our technicians at 703-260-1148 for assistance.
  6. One light is flickering on, on and off while the other flashes on, off, on. This indicates there may be an issue with your heater’s motherboard or wiring. Air-Right Energy Design, Inc. can pinpoint the problem and repair it.
  7. Both lights are using alternating slow flashes. This indicates your HVAC equipment possibly has a flame problem. There may be an issue with its gas supply, gas valve or ignitor control. Call us at 703-260-1148 for support.
  8. A single light flickers slowly while the other is continuous. This typically means your heater’s limit switch is malfunctioning. The switch prevents your heater from overheating. Contact the specialists at Air-Right Energy Design, Inc. for support.

Heating System Blower Runs But No Heat

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

  • The duo of lights are showing alternate fast blinks. This signifies your furnace ignitor might not be working. This part lights energy in your heater to make warm air and should be repaired by a technician from Air-Right Energy Design, Inc..

Turn to Us for Professional Furnace Repair

When you need to have your heating system repaired quickly, trust the experts at Air-Right Energy Design, Inc.. Our techs will take care of the problem right away and have your home feeling cozy again soon. Get in touch with us at 703-260-1148 or contact us online to get an appointment right away.

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