Furnace troubleshooting

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

While your Lennox® heating system isn’t able to speak to you, it does have a way to communicate a furnace error.

Its motherboard has double LED lights that can show a fault code. Based on the fault, your furnace might show solid or flashing lights.

While there are various basic furnace repairs you can do yourself, many tasks are best taken care of by the professionals. When your heating system will not start or deliver warmth, reach out to House of Heating Incorporated at 715-384-3163 for expert furnace repair in Marshfield.

Our specialists will rapidly detect and fix the failure, even if you don’t use a Lennox heater. We can fix any brands or makes—and get the heat reintroduced to your residence fast.


What Does the Flickering Light on My Heating System Mean?

Your heater relies on lights to flash code when it is malfunctioning. It also uses this setup to tell you it’s working correctly.

Correct function consists of:

  • Concurrent slow flash—heating system operating correctly.
  • Both lights flash fast—heating system is initiating the call for heat.

If you notice a single light flashing slowly and the other going on and off fast, your heating system could have a low flame signal. This can take place even when your furnace is heating correctly. It signifies the flame sensing rod could need to be cleaned or in the bad spot on the burner. Contact us at 715-384-3163 for support.

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

Furnace Won’t Turn On

Here are many of the light patterns you may see when your heating system will not or keep heating. The bulk of these issues have to be handled by a specialist, like one from House of Heating Incorporated.

  1. The duo of LED lights aren’t lit. This indicates your heater might not be receiving power. Examine the breaker box to ensure the heating system fuse isn’t flipped. Try resetting the fuse if it is in the “off” position. If it promptly flips after you reset it, leave the breaker alone and call us at 715-384-3163.
  2. One light is stable and the other is blinking slowly. This means the flame rollout switch is probably not working right. The switch is a critical safety guard that aids in avoiding fires and carbon monoxide. You shouldn’t attempt to fix this issue yourself.
  3. An individual light is blinking quickly and the other is flashing slowly. This typically signifies power polarity has been inverted. Your furnace could have a wiring fault that calls for professional aid from House of Heating Incorporated.
  4. All lights are flashing slowly. This signifies your heater’s blower motor probably isn’t running. This part moves hot air from the heater into your home. We can aid in figuring out what’s wrong with this piece.
  5. An individual light is blinking slowly and the other is flickering quickly. This signifies your furnace could have insufficient voltage or a short circuit. Contact our experts at 715-384-3163 for assistance.
  6. One light is flashing on, on and off while the other flashes on, off, on. This signifies there might be an issue with your heating system’s control board or wiring. House of Heating Incorporated can pinpoint the problem and handle it.
  7. Both lights display alternating slow blinks. This indicates your HVAC system possibly has a flame error. There might be an issue with its gas supply, gas valve or ignitor control. Reach out to us at 715-384-3163 for support.
  8. An individual light flickers slowly while the other stays solid. This often means your heater’s limit switch is not working. The switch keeps your heating system from becoming too warm. Call the pros at House of Heating Incorporated for help.

Heater Blower Works But No Warmth

Here’s what could be at fault when you hear your heating system’s blower fan on, but you aren’t gaining any warm air.

  • The pair of lights display every other rapid flickers. This indicates your furnace ignitor could not be in working order. This component lights energy in your furnace to create warm air and should be repaired by a technician from House of Heating Incorporated.

Turn to Us for Expert Furnace Repair

When you need to get your furnace repaired without delay, depend on the technicians at House of Heating Incorporated. Our techs will repair the issue promptly and have your space feeling comfortable again soon. Get in touch with us at 715-384-3163 or contact us online to get an appointment right away.

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