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

December 06, 2019

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

Its motherboard has two LED lights that can show a fault code. Subject to the issue, your furnace might display continuous or flashing lights.

While there are various basic HVAC repairs you can take care of on your own, the majority of fixes are best taken care of by the professionals. When your furnace will not start or give warm air, reach out to Wallpe Heating & Cooling at 812-663-7252 for expert furnace repair in Greensburg.

Our specialists will swiftly determine and repair the issue, even if you don’t own a Lennox heating system. We can service any kinds or makes—and get the heat restored to your residence fast.


What Does the Flickering Light on My Furnace Mean?

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

Normal heating consists of:

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

If you notice a lone light going on and off slowly and the other flashing quickly, your heating system might be experiencing a low flame signal. This can happen even when your furnace is operating correctly. It means the flame sensing rod may have build-up or in the wrong area on the burner. Contact us at 812-663-7252 for support.

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

Heater Will Not Start

Here are a few of the light sequences you may observe when your furnace won’t turn on or keep operating. The bulk of these errors must be handled 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. Look at the breaker box to ensure the furnace fuse is not triggered. Attempt to reset 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. A single light is unchanging and the other is blinking slowly. This shows 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 inverted. Your furnace could have a wiring error that calls for expert help from Wallpe Heating & Cooling.
  4. Both lights are flashing slowly. This signifies your furnace’s blower motor likely isn’t running. This component circulates warm air from the HVAC system into your home. We can assist in determining what’s causing a problem with this piece.
  5. An individual light is blinking slowly and the other is flashing quickly. This means your heater might have not enough voltage or a short circuit. Call our specialists at 812-663-7252 for support.
  6. One light is blinking on, on and off while the other blinks on, off, on. This indicates there may be a malfunction with your heater’s control panel or wiring. Wallpe Heating & Cooling can find the issue and repair it.
  7. Both lights display alternating slow flickers. This signifies your heater 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 remains solid. This often indicates your heater’s limit switch is not working. The switch stops your HVAC equipment from overheating. Contact the professionals at Wallpe Heating & Cooling for assistance.

Heating System Blower Works But No Heat

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

  • The duo of lights display alternating fast blinks. This signifies your furnace ignitor may not be working. This part kindles energy in your heating system to produce warm air and should be serviced by a specialist from Wallpe Heating & Cooling.

Depend on Us for Professional Furnace Repair

When you have to have your furnace fixed without delay, depend on the professionals at Wallpe Heating & Cooling. Our technicians will handle the issue quickly and have your residence feeling comfortable again in no time. Reach out to us at 812-663-7252 or contact us online to schedule an appointment today.