Furnace troubleshooting

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

While your Lennox® heater can’t chat with you, it does have a process to get your attention when there’s a furnace error.

Its control board has two LED lights that can share a fault code. Subject to the malfunction, your heating system might use steady or flashing lights.

Although there are certain simple HVAC fixes you can take care of on your own, the majority of fixes are best handled by the professionals. When your furnace will not turn on or provide heated air, get in touch with Keystone Heating & Air Conditioning Co., Inc at 262-358-9468 for experienced furnace repair in Racine.

Our technicians will rapidly diagnose and fix the problem, even if you don’t own a Lennox heater. We can fix all types or models—and get the heat restored to your house fast.


What Does the Flickering Light on My Heating System Mean?

Your furnace relies on lights to flash code when it needs to be repaired. It also works this system to let you know it’s running correctly.

Correct function involves:

  • Both lights flash slowly—furnace heating correctly.
  • Both lights flash fast—heater is beginning to call for heat.

If you notice a lone light blinking slowly and the other blinking rapidly, your furnace could have a low flame signal. This can happen even when your heating system is operating like it should. It means the flame sensing rod may have build-up or in the wrong location on the burner. Call us at 262-358-9468 for assistance.

Here are several other of the most routine faults for Lennox heating systems.

Furnace Won’t Kick On

Here are many of the light sequences you might observe when your heating system won’t turn on or keep heating. The majority of these errors have to be taken care of by a specialist, like one from Keystone Heating & Air Conditioning Co., Inc.

  1. The duo of LED lights aren’t lit. This means your heater might not have electricity. Examine the breaker box to confirm the heating system fuse isn’t triggered. Try resetting the fuse if it is in the “off” area. If it immediately turns off following a reset, don’t try to reset it again and call us at 262-358-9468.
  2. An individual light is unchanging and the other is flickering slowly. This implies the flame rollout switch is may be open. The part is a critical safety mechanism that helps in stopping fires and carbon monoxide. You shouldn’t try to handle this problem yourself.
  3. One light is flickering quickly and the other is flashing slowly. This typically means power polarity has been reversed. Your furnace could have a wiring error that calls for specialized assistance from Keystone Heating & Air Conditioning Co., Inc.
  4. Both lights are flashing slowly. This means your heater’s blower motor likely isn’t working. This component circulates hot air from the furnace into your space. We can help in figuring out what’s causing an issue with this part.
  5. One light is blinking slowly and the other is flashing quickly. This signifies your furnace may have low voltage or a short circuit. Contact our technicians at 262-358-9468 for help.
  6. One light is flashing on, on and off while the other blinks on, off, on. This means there may be a problem with your heater’s control panel or wiring. Keystone Heating & Air Conditioning Co., Inc can find the issue and handle it.
  7. The duo of lights are using alternate slow blinks. This signifies your HVAC system likely has a flame error. There might be a problem with its gas supply, gas valve or ignitor control. Reach out to us at 262-358-9468 for support.
  8. One light flashes slowly while the other stays steady. This often means your HVAC equipment’s limit switch is not working. The switch keeps your HVAC system from overheating. Contact the professionals at Keystone Heating & Air Conditioning Co., Inc for assistance.

Heater Blower Operates But No Heat

Here’s what may be broken when you observe your furnace’s blower fan working, but you aren’t receiving any warm air.

  • The pair of lights are giving alternating quick flickers. This means your furnace ignitor might be broken. This piece kindles energy in your heater to produce warm air and should be serviced by a specialist from Keystone Heating & Air Conditioning Co., Inc.

Trust Us for Professional Furnace Repair

When you need to have your heater in working order fast, depend on the professionals at Keystone Heating & Air Conditioning Co., Inc. Our pros will fix the problem without delay and have your house feeling comfortable again in no time. Reach out to us at 262-358-9468 or contact us online to request an appointment today.

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