Furnace troubleshooting

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

While your Lennox® furnace isn’t able to talk to you, it possesses a process to tell you about a furnace error.

Its control panel has two LED lights that can show a fault code. Based on the failure, your furnace could show continuous or flashing lights.

While there are various basic heating repairs you can take care of without an expert, most fixes are best taken care of by the professionals. When your furnace will not start or provide warm air, call Wallpe Heating & Cooling at 812-663-7252 for experienced furnace repair in Greensburg.

Our specialists will swiftly spot and repair the failure, even if you don’t own a Lennox heater. We can repair any kinds or models—and get the heat restored to your house fast.


What Does the Flashing Light on My Furnace Mean?

Your heater relies on lights to flash code when it isn’t working right. It also uses this system to tell you it’s heating properly.

Normal function consists of:

  • Concurrent slow flash—heating system running like it should.
  • Both lights flash fast—furnace is starting to call for heat.

If you notice a lone light going on and off slowly and the other flashing quickly, your heater might have a low flame signal. This can happen even when your furnace is operating correctly. It means the flame sensing rod could need to be cleaned or in the wrong location on the burner. Reach out to us at 812-663-7252 for support.

Here are a few other of the most common errors for Lennox HVAC systems.

Heating System Will Not Kick On

Here are a few of the light patterns you may observe when your furnace won’t turn on or keep operating. Most of these errors need to be fixed by a technician, such as one from Wallpe Heating & Cooling.

  1. Both LED lights are extinguished. This indicates your HVAC system might not have power. Examine the breaker box to confirm the furnace fuse is not triggered. Try resetting the fuse if it has moved into the “off” spot. If it promptly flips after you reset it, leave the breaker alone and contact us at 812-663-7252.
  2. An individual light is unchanging and the other is blinking slowly. This means the flame rollout switch is possibly malfunctioning. The switch is an important safety device that helps in preventing fires and carbon monoxide. You shouldn’t attempt to fix this problem yourself.
  3. One light is flashing fast and the other is flashing slowly. This often means power polarity has been transposed. Your furnace might have a wiring error that needs specialized support from Wallpe Heating & Cooling.
  4. The pair of lights are flashing slowly. This indicates your furnace’s blower motor possibly isn’t operating. This component moves warm air from the HVAC system into your home. We can assist in determining what’s causing an issue with this piece.
  5. A single light is flickering slowly and the other is flashing quickly. This means your heater might have insufficient voltage or a short circuit. Reach out to our specialists at 812-663-7252 for assistance.
  6. One light is blinking on, on and off while the other flickers on, off, on. This indicates there may be a malfunction with your heater’s motherboard or wiring. Wallpe Heating & Cooling can find the issue and take care of it.
  7. Both lights display alternating slow blinks. This signifies your heating system may have a flame problem. There might be trouble with its gas supply, gas valve or ignitor control. Contact us at 812-663-7252 for assistance.
  8. One light flashes slowly while the other stays solid. This typically signifies your heater’s limit switch is not working. The switch keeps your HVAC equipment from getting too hot. Contact the professionals at Wallpe Heating & Cooling for assistance.

Heater Blower Operates But No Heat

Here’s what may be wrong when you observe your heating equipment’s blower fan on, but you aren’t gaining any warmth.

  • The pair of lights display alternating fast blinks. This signifies your furnace ignitor may be broken. This part lights energy in your heating system to produce warmth and should be serviced by a specialist from Wallpe Heating & Cooling.

Depend on Us for Skilled Furnace Repair

When you have to have your furnace fixed fast, trust the specialists at Wallpe Heating & Cooling. Our technicians will handle the issue quickly and have your house feeling comfortable again in no time. Call us at 812-663-7252 or contact us online to schedule an appointment today.

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