Furnace troubleshooting

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

While your Lennox® furnace can’t speak to you, it has a procedure to get your attention when there’s a furnace error.

Its control panel has twin LED lights that can show a fault code. Depending on the fault, your heater might show solid or flashing lights.

Although there are various basic furnace adjustments you can do yourself, most repairs are best handled by the professionals. When your furnace refuses to kick on or provide heat, call Kapaun & Brown Inc. at 641-753-3563 for skilled furnace repair in Marshalltown.

Our technicians will swiftly pinpoint and handle the malfunction, even if you don’t own a Lennox furnace. We can service all kinds or models—and get the comfort restored to your residence without delay.


What Does the Flashing Light on My Furnace Mean?

Your furnace relies on lights to flash code when it needs to be repaired. It also works these lights to tell you it’s running correctly.

Regular function consists of:

  • Simultaneous slow flash—heating system operating correctly.
  • Simultaneous fast flash—heater is starting to call for heat.

If you notice a lone light going on and off slowly and the other going on and off quickly, your heating system may be experiencing a low flame signal. This can happen even when your heater is operating properly. It indicates the flame sensing rod might need to be cleaned or in the wrong location on the burner. Call us at 641-753-3563 for assistance.

Here are some of the most common faults for Lennox furnaces.

Furnace Won’t Turn On

Here are many of the light arrangements you could see when your heat refuses to or keep running. The bulk of these problems need to be repaired by a technician, such as one from Kapaun & Brown Inc..

  1. The duo of LED lights are extinguished. This means your HVAC system might not have power. Go to the breaker box to make sure the heating system fuse is not flipped. You should reset the fuse if it’s in the “off” position. If it instantly flips following a reset, leave the breaker alone and get in touch with us us at 641-753-3563.
  2. A single light is stable and the other is flashing slowly. This means the flame rollout switch is probably not working right. The part is an essential safety device that helps in preventing fires and carbon monoxide. You shouldn’t seek to repair this malfunction yourself.
  3. A single light is flashing quickly and the other is blinking slowly. This usually indicates power polarity has been transposed. Your heating system might have a wiring problem that calls for expert support from Kapaun & Brown Inc..
  4. All lights are flickering slowly. This signifies your furnace’s blower motor possibly isn’t working. This part sends heated air from the heating system into your rooms. We can help in determining what’s causing an issue with this piece.
  5. A single light is flickering slowly and the other is flickering rapidly. This signifies your heating system might have insufficient voltage or a short circuit. Call our specialists at 641-753-3563 for support.
  6. One light is blinking on, on and off while the other flashes on, off, on. This signifies there might be an error with your heating system’s motherboard or wiring. Kapaun & Brown Inc. can determine the fault and handle it.
  7. The pair of lights display alternate slow blinks. This indicates your HVAC system may have a flame failure. There may be an issue with its gas supply, gas valve or ignitor control. Reach out to us at 641-753-3563 for assistance.
  8. A single light flickers slowly while the other is continuous. This typically indicates your heater’s limit switch is experiencing an error. The switch stops your HVAC system from overheating. Contact the pros at Kapaun & Brown Inc. for assistance.

Furnace Blower Works But No Heat

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

  • The duo of lights display every other quick blinks. This indicates your furnace ignitor may not be working. This component ignites fuel in your furnace to create warm air and should be repaired by a technician from Kapaun & Brown Inc..

Turn to Us for Professional Furnace Repair

When you need to get your furnace repaired quickly, depend on the technicians at Kapaun & Brown Inc.. Our techs will take care of the error quickly and have your space feeling relaxing again soon. Get in touch with us at 641-753-3563 or contact us online to request an appointment now.

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