Furnace troubleshooting

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

While your Lennox® HVAC equipment isn’t able to talk to you, it possesses a process to get your attention when there’s a furnace error.

Its motherboard has twin LED lights that can display a fault code. Depending on the problem, your furnace might display solid or flashing lights.

Though there are various simple heating adjustments you can take care of yourself, most services are best left to HVAC technicians. When your heating system will not kick on or provide heated air, contact McNatt Inc at 361-247-0605 for expert furnace repair in Robstown.

Our experts will speedily determine and handle the malfunction, even if you don’t have a Lennox heater. We can service all kinds or configuration—and get the comfort reintroduced to your home fast.


What Does the Flashing Light on My Furnace Mean?

Your heating system relies on lights to flash code when it needs to be repaired. It also uses this setup to tell you it’s heating properly.

Correct heating involves:

  • Simultaneous slow flash—heater working correctly.
  • Concurrent fast flash—heater is beginning to call for heat.

If you see a single light going on and off slowly and the other flashing quickly, your heater could be experiencing a low flame signal. This can take place even when your furnace is running correctly. It signifies the flame sensing rod could need to be cleaned or in the incorrect area on the burner. Contact us at 361-247-0605 for support.

Here are a few other of the most routine faults for Lennox furnaces.

Heater Will Not Turn On

Here are a few of the light arrangements you may notice when your heating system won’t turn on or stay on. The bulk of these issues must be repaired by a technician, for instance from McNatt Inc.

  1. The pair of LED lights are off. This indicates your heating system might not be receiving power. Examine the breaker box to make sure the furnace fuse hasn’t flipped. Attempt to reset the fuse if it’s in the “off” position. If it rapidly turns off following a reset, leave the breaker alone and get in touch with us us at 361-247-0605.
  2. A single light is solid and the other is flickering slowly. This shows the flame rollout switch is likely open. The part is an important safety guard that assists in preventing fires and carbon monoxide. You shouldn’t seek to fix this issue on your own.
  3. A single light is flashing fast and the other is flashing slowly. This likely signifies power polarity has been inverted. Your heating system might have a wiring error that needs specialized assistance from McNatt Inc.
  4. All lights are flickering slowly. This means your furnace’s blower motor probably isn’t running. This piece sends heated air from the heating system into your space. We can help in pinpointing what’s wrong with this piece.
  5. An individual light is blinking slowly and the other is blinking rapidly. This indicates your furnace could have not enough voltage or a short circuit. Get in touch with our experts at 361-247-0605 for help.
  6. One light is flashing on, on and off while the other flickers on, off, on. This signifies there could be a fault with your furnace’s motherboard or wiring. McNatt Inc can pinpoint the fault and take care of it.
  7. Both lights display every other slow flashes. This signifies your HVAC system possibly has a flame error. There may be trouble with its gas supply, gas valve or ignitor control. Contact us at 361-247-0605 for support.
  8. One light blinks slowly while the other remains continuous. This typically indicates your heating system’s limit switch is malfunctioning. The switch stops your HVAC system from becoming too warm. Contact the experts at McNatt Inc for help.

Heater Blower Operates But No Heat

Here’s what might be at fault when you hear your heater’s blower fan running, but you aren’t receiving any warmth.

  • The pair of lights display alternating quick flashes. This signifies your furnace ignitor could not be working. This piece ignites energy in your furnace to make heat and should be serviced by a professional from McNatt Inc.

Turn to Us for Expert Furnace Repair

When you need to get your HVAC equipment fixed fast, trust the technicians at McNatt Inc. Our technicians will handle the fault quickly and have your house feeling cozy again in a short time. Contact us at 361-247-0605 or contact us online to request an appointment today.

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