Furnace troubleshooting

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

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

Its control panel has twin LED lights that can display a fault code. Depending on the malfunction, your furnace might show steady or flashing lights.

Though there are some basic heating fixes you can take care of yourself, most services are best handled by experts. When your heater will not start or give heated air, contact McNatt Inc at 361-247-0605 for experienced furnace repair in Robstown.

Our specialists will quickly spot and handle the malfunction, even if you don’t have a Lennox heater. We can repair all types or configuration—and get the warmth returned to your home fast.


What Does the Flickering Light on My Furnace Mean?

Your heating system depends on lights to flash code when it is malfunctioning. It also uses this setup to tell you it’s heating properly.

Regular heating involves:

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

If you see a single light blinking slowly and the other flashing quickly, your heater might have a low flame signal. This can occur even when your furnace is running correctly. It signifies the flame sensing rod could need to be cleaned or in the incorrect location on the burner. Reach out to us at 361-247-0605 for support.

Here are a few other of the most typical issues for Lennox heating systems.

Heater Refuses to Turn On

Here are a few of the light arrangements you may observe when your heating system won’t turn on or stay on. Most 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 furnace might not be receiving power. Look at the breaker box to make sure the furnace fuse hasn’t triggered. Try resetting the fuse if it’s in the “off” position. If it rapidly turns off after a subsequent reset, leave the breaker alone and get in touch with us us at 361-247-0605.
  2. An individual light is unchanging and the other is flickering slowly. This shows the flame rollout switch is likely open. The component is an important safety guard that aids in preventing fires and carbon monoxide. You shouldn’t seek to take care of this issue without professional help.
  3. An individual light is flashing rapidly and the other is flashing slowly. This likely indicates power polarity has been transposed. Your heating system might have a wiring error that calls for expert assistance from McNatt Inc.
  4. All lights are blinking slowly. This means your furnace’s blower motor probably isn’t operating. This piece sends hot air from the heating system into your space. We can help in figuring out what’s wrong with this component.
  5. An individual light is flickering slowly and the other is blinking rapidly. This signifies your furnace might have insufficient 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 blinks on, off, on. This indicates there might be a fault with your furnace’s control panel or wiring. McNatt Inc can pinpoint the issue and repair it.
  7. Both lights display every other slow flashes. This indicates your HVAC system possibly has a flame error. There might 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 keeps your furnace from becoming too warm. Get in touch with the experts at McNatt Inc for help.

Heating System Blower Works But No Heat

Here’s what may be at fault when you notice your heater’s blower fan running, but you aren’t getting any warmth.

  • The pair of lights display alternating rapid flashes. This indicates your furnace ignitor might be broken. This component ignites energy in your heating system to make heat and should be serviced by a professional from McNatt Inc.

Depend on Us for Expert Furnace Repair

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

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