Furnace troubleshooting

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

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

Its motherboard has a set of LED lights that can share a fault code. Depending on the issue, your furnace could display continuous or flashing lights.

Though there are a few elementary HVAC repairs you can complete yourself, most repairs are best taken care of by experts. When your heater will not turn on or provide warmth, get in touch with Gillman Heating and Air at 478-202-3076 for professional furnace repair in Perry.

Our specialists will rapidly identify and repair the problem, even if you don’t use a Lennox heater. We can repair all types or configuration—and get the heat returned to your residence quickly.


What Does the Flashing Light on My Heating System Mean?

Your furnace relies on lights to flash code when it requires repairs. It also uses this setup to tell you it’s operating correctly.

Normal operation involves:

  • Simultaneous slow flash—heater working correctly.
  • Simultaneous fast flash—heating system is initiating the call for heat.

If you see a lone light flashing slowly and the other going on and off rapidly, your heater might be having a low flame signal. This can take place even when your furnace is heating like it should. It signifies the flame sensing rod may have build-up or in the bad area on the burner. Call us at 478-202-3076 for assistance.

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

Heating System Will Not Kick On

Here are some of the light patterns you may observe when your furnace will not or stay on. The bulk of these errors must be taken care of by a professional, for instance from Gillman Heating and Air.

  1. Both LED lights are off. This indicates your heater might not have electricity. Look at the breaker box to ensure the heating system fuse has not flipped. Try resetting the fuse if it’s in the “off” position. If it promptly trips after a subsequent reset, don’t try to reset it again and get in touch with us us at 478-202-3076.
  2. An individual light is stable and the other is flickering slowly. This shows the flame rollout switch is likely malfunctioning. The switch is an important safety guard that assists in avoiding fires and carbon monoxide. You shouldn’t attempt to take care of this fault yourself.
  3. An individual light is flashing fast and the other is flickering slowly. This likely indicates power polarity has been transposed. Your heater might have a wiring fault that calls for expert aid from Gillman Heating and Air.
  4. The duo of lights are flickering slowly. This signifies your furnace’s blower motor likely isn’t operating. This component circulates warm air from the HVAC system into your house. We can aid in pinpointing what’s causing a problem with this piece.
  5. An individual light is flickering slowly and the other is blinking quickly. This signifies your heating system may have not enough voltage or a short circuit. Call our specialists at 478-202-3076 for support.
  6. One light is blinking on, on and off while the other flashes on, off, on. This indicates there might be an issue with your furnace’s control board or wiring. Gillman Heating and Air can determine the fault and take care of it.
  7. The pair of lights show alternate slow flashes. This means your heating system likely has a flame error. There could be an issue with its gas supply, gas valve or ignitor control. Call us at 478-202-3076 for support.
  8. An individual light blinks slowly while the other stays solid. This typically indicates your heating system’s limit switch is open. The switch keeps your furnace from becoming too warm. Reach out to the professionals at Gillman Heating and Air for support.

Furnace Blower Works But No Warmth

Here’s what may be at fault when you notice your heating system’s blower fan working, but you aren’t receiving any warmth.

  • The duo of lights display alternating fast blinks. This indicates your furnace ignitor could not be working. This part kindles energy in your furnace to make warm air and should be repaired by a technician from Gillman Heating and Air.

Turn to Us for Skilled Furnace Repair

When you need to have your HVAC equipment fixed quickly, trust the professionals at Gillman Heating and Air. Our techs will take care of the problem quickly and have your home feeling comfortable again soon. Get in touch with us at 478-202-3076 or contact us online to get an appointment right away.

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