Furnace troubleshooting

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

While your Lennox® heater cannot speak to you, it has a process to tell you about a furnace error.

Its control panel has two LED lights that can show a fault code. Depending on the problem, your heating system may use continuous or flashing lights.

While there are some elementary furnace repairs you can do on your own, most tasks are best handled by the professionals. When your furnace refuses to start or provide warm air, contact Dave's Diversified Services at 540-369-3971 for experienced furnace repair in Front Royal.

Our technicians will quickly discover and handle the breakdown, even if you don’t own a Lennox heater. We can repair all types or configuration—and get the warmth returned to your home quickly.


What Does the Flashing Light on My Furnace Mean?

Your heating system depends on lights to flash code when it requires repairs. It also works this system to tell you it’s operating correctly.

Normal function includes:

  • Both lights flash slowly—heating system working properly.
  • Both lights flash fast—heater is initiating the call for heat.

If you realize that a solitary light blinking slowly and the other going on and off quickly, your heating system could be having a low flame signal. This can take place even when your heating system is running like it should. It indicates the flame sensing rod might have build-up or in the wrong area on the burner. Reach out to us at 540-369-3971 for support.

Here are several other of the most typical errors for Lennox heaters.

Heating System Will Not Start

Here are a few of the light arrangements you might see when your heating system refuses to or keep operating. The majority of these problems need to be fixed by a technician, such as one from Dave's Diversified Services.

  1. The pair of LED lights aren’t lit. This signifies your heating system might not be receiving power. Find the breaker box to make sure the heating system fuse is not tripped. Try resetting the fuse if it is in the “off” position. If it immediately trips after a subsequent reset, don’t touch the breaker and get in touch with us us at 540-369-3971.
  2. A single light is solid and the other is flickering slowly. This means the flame rollout switch is likely open. The part is an important safety tool that aids in preventing fires and carbon monoxide. You shouldn’t try to handle this fault without professional help.
  3. An individual light is flickering quickly and the other is flashing slowly. This usually signifies power polarity has been reversed. Your heater could have a wiring error that requires professional help from Dave's Diversified Services.
  4. The pair of lights are flickering slowly. This indicates your furnace’s blower motor probably isn’t working. This part distributes warm air from the heater into your rooms. We can aid in pinpointing what’s wrong with this piece.
  5. An individual light is flashing slowly and the other is flickering rapidly. This means your heater might have low voltage or a short circuit. Contact our professionals at 540-369-3971 for assistance.
  6. One light is flickering on, on and off while the other blinks on, off, on. This indicates there might be an issue with your heating system’s motherboard or wiring. Dave's Diversified Services can determine the issue and repair it.
  7. The duo of lights show alternating slow flashes. This means your heater likely has a flame failure. There may be trouble with its gas supply, gas valve or ignitor control. Get in touch with us at 540-369-3971 for assistance.
  8. A single light flickers slowly while the other remains continuous. This often means your HVAC equipment’s limit switch is open. The switch prevents your HVAC equipment from getting too hot. Reach out to the pros at Dave's Diversified Services for support.

Heater Blower Works But No Warm Air

Here’s what may be wrong when you hear your heater’s blower fan running, but you aren’t getting any warm air.

  • The pair of lights are showing alternate rapid flashes. This means your furnace ignitor may not be in working order. This piece kindles energy in your heater to produce warm air and should be serviced by a professional from Dave's Diversified Services.

Turn to Us for Skilled Furnace Repair

When you need to get your furnace repaired fast, turn to the professionals at Dave's Diversified Services. Our techs will take care of the fault right away and have your home feeling relaxing again in no time. Contact us at 540-369-3971 or contact us online to request an appointment now.

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