Furnace troubleshooting

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

While your Lennox® HVAC equipment cannot chat with you, it has a process to tell you about a furnace error.

Its motherboard has a set of LED lights that can display a fault code. Depending on the issue, your furnace could display solid or flashing lights.

Though there are some simple furnace repairs you can do on your own, the majority of fixes are best left to HVAC technicians. When your heating system refuses to start or provide warm air, get in touch with Knoechel Heating Company at 724-425-5852 for expert furnace repair in Zelienople.

Our experts will rapidly spot and handle the issue, even if you don’t use a Lennox furnace. We can fix whichever types or models—and get the warmth returned to your house without delay.


What Does the Flickering Light on My Heating System Mean?

Your heater uses lights to flash code when it needs to be repaired. It also engages these lights to relay it’s running properly.

Regular operation involves:

  • Concurrent slow flash—furnace running properly.
  • Concurrent fast flash—heating system is starting to call for heat.

If you see a single light blinking slowly and the other blinking quickly, your furnace could be having a low flame signal. This can happen even when your heating system is heating properly. It indicates the flame sensing rod may have build-up or in the incorrect area on the burner. Contact us at 724-425-5852 for assistance.

Here are several other of the most common problems for Lennox furnaces.

Furnace Refuses to Kick On

Here are a few of the light patterns you could notice when your heating system refuses to or keep operating. The bulk of these issues must be repaired by a technician, like one from Knoechel Heating Company.

  1. Both LED lights aren’t lit. This indicates your furnace might not have electricity. Examine the breaker box to make sure the furnace fuse is not flipped. Try resetting the fuse if it has moved into the “off” area. If it immediately flips after a subsequent reset, don’t touch the breaker and contact us at 724-425-5852.
  2. A single light is stable and the other is blinking slowly. This implies the flame rollout switch is possibly open. The switch is an important safety guard that assists in stopping fires and carbon monoxide. You shouldn’t attempt to fix this malfunction on your own.
  3. A single light is flashing rapidly and the other is flashing slowly. This usually indicates power polarity has been transposed. Your furnace might have a wiring problem that calls for specialized support from Knoechel Heating Company.
  4. The pair of lights are flashing slowly. This means your furnace’s blower motor possibly isn’t operating. This piece sends hot air from the furnace into your house. We can aid in figuring out what’s wrong with this part.
  5. One light is blinking slowly and the other is flashing rapidly. This signifies your furnace may have low voltage or a short circuit. Get in touch with our specialists at 724-425-5852 for assistance.
  6. One light is flashing on, on and off while the other flickers on, off, on. This means there may be a problem with your furnace’s motherboard or wiring. Knoechel Heating Company can find the issue and repair it.
  7. The pair of lights display alternating slow flickers. This means your HVAC system likely has a flame issue. There might be a problem with its gas supply, gas valve or ignitor control. Reach out to us at 724-425-5852 for assistance.
  8. A single light blinks slowly while the other stays continuous. This typically indicates your HVAC system’s limit switch is malfunctioning. The switch stops your heating system from getting too hot. Call the professionals at Knoechel Heating Company for support.

Furnace Blower Works But No Warm Air

Here’s what might be broken when you observe your heating system’s blower fan running, but you aren’t getting any warmth.

  • The duo of lights are showing alternate fast flickers. This means your furnace ignitor could not be in working order. This part ignites energy in your heater to produce heat and should be serviced by a professional from Knoechel Heating Company.

Trust Us for Expert Furnace Repair

When you have to get your heater in working order quickly, depend on the experts at Knoechel Heating Company. Our technicians will fix the error quickly and have your residence feeling relaxing again soon. Get in touch with us at 724-425-5852 or contact us online to request an appointment now.

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