Furnace troubleshooting

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

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

Its control panel has a set of LED lights that can display a fault code. Based on the fault, your furnace could display steady or flashing lights.

While there are some elementary HVAC fixes you can complete yourself, the majority of services are best left to HVAC technicians. When your heater will not start or deliver warm air, get in touch with O'Brien Heating & Air Conditioning at 610-257-7035 for experienced furnace repair in Drexel Hill.

Our experts will rapidly pinpoint and fix the issue, even if you don’t own a Lennox heating system. We can repair all brands or configuration—and get the heat restored to your house without delay.


What Does the Flickering Light on My Heater Mean?

Your heater uses lights to flash code when it is malfunctioning. It also works this system to tell you it’s heating like it should.

Normal heating includes:

  • Simultaneous slow flash—furnace operating like it should.
  • Simultaneous fast flash—heating system is beginning to call for heat.

If you realize that a lone light flashing slowly and the other going on and off rapidly, your heating system might have a low flame signal. This can happen even when your furnace is heating like it should. It signifies the flame sensing rod could have build-up or in the incorrect spot on the burner. Reach out to us at 610-257-7035 for help.

Here are some of the most typical problems for Lennox heating systems.

Heating System Won’t Turn On

Here are some of the light patterns you may notice when your heater refuses to or keep running. The bulk of these problems have to be taken care of by a technician, such as one from O'Brien Heating & Air Conditioning.

  1. The pair of LED lights aren’t lit. This means your heater might not have power. Find the breaker box to ensure the furnace fuse has not triggered. Attempt to reset the fuse if it is in the “off” spot. If it immediately flips after you reset it, leave the breaker alone and get in touch with us us at 610-257-7035.
  2. A single light is continuous and the other is blinking slowly. This shows the flame rollout switch is may be open. The switch is a critical safety tool that helps in preventing fires and carbon monoxide. You shouldn’t seek to handle this problem on your own.
  3. One light is blinking rapidly and the other is flashing slowly. This usually indicates power polarity has been inverted. Your heating system might have a wiring problem that needs expert help from O'Brien Heating & Air Conditioning.
  4. Both lights are blinking slowly. This signifies your heater’s blower motor likely isn’t running. This piece moves warm air from the furnace into your residence. We can assist in pinpointing what’s wrong with this piece.
  5. An individual light is flashing slowly and the other is flickering rapidly. This indicates your HVAC system could have not enough voltage or a short circuit. Get in touch with our specialists at 610-257-7035 for assistance.
  6. One light is flashing on, on and off while the other flashes on, off, on. This means there might be trouble with your heating system’s control board or wiring. O'Brien Heating & Air Conditioning can locate the fault and take care of it.
  7. The pair of lights show alternate slow blinks. This signifies your furnace may have a flame problem. There may be a problem with its gas supply, gas valve or ignitor control. Reach out to us at 610-257-7035 for support.
  8. An individual light blinks slowly while the other remains steady. This often means your HVAC equipment’s limit switch is malfunctioning. The switch stops your HVAC equipment from overheating. Contact the professionals at O'Brien Heating & Air Conditioning for assistance.

Furnace Blower Runs But No Warm Air

Here’s what might be wrong when you hear your furnace’s blower fan working, but you aren’t gaining any heated air.

  • The pair of lights display alternate fast flickers. This signifies your furnace ignitor might not be working. This piece lights energy in your HVAC equipment to create warmth and should be repaired by a professional from O'Brien Heating & Air Conditioning.

Trust Us for Skilled Furnace Repair

When you have to have your HVAC equipment repaired fast, turn to the professionals at O'Brien Heating & Air Conditioning. Our pros will repair the error promptly and have your house feeling relaxing again in no time. Call us at 610-257-7035 or contact us online to schedule an appointment right away.

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