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

December 06, 2019

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

Its control panel has two LED lights that can display a fault code. Subject to the issue, your heating system might use continuous or flashing lights.

Although there are certain simple furnace adjustments you can take care of without an expert, many fixes are best handled by the professionals. When your heater will not kick on or provide warmth, get in touch with Age Heating & Cooling at 208-578-4258 for professional furnace repair in Sandpoint.

Our experts will quickly determine and take care of the issue, even if you don’t own a Lennox heating system. We can service whichever types or makes—and get the heat reintroduced to your residence quickly.


What Does the Flashing Light on My Heating System Mean?

Your furnace relies on lights to flash code when it requires repairs. It also engages this setup to tell you it’s operating properly.

Regular function includes:

  • Both lights flash slowly—heating system working correctly.
  • Both lights flash fast—heater is beginning to call for heat.

If you realize that a lone light blinking slowly and the other flashing fast, your heating system may have a low flame signal. This can occur even when your heater is working like it should. It signifies the flame sensing rod could have build-up or in the wrong spot on the burner. Contact us at 208-578-4258 for support.

Here are a few other of the most typical issues for Lennox heaters.

Heater Won’t Start

Here are a few of the light arrangements you may see when your heater refuses to or keep heating. Most of these errors need to be repaired by a professional, for instance from Age Heating & Cooling.

  1. The duo of LED lights are off. This signifies your heating system might not have electricity. Look at the breaker box to confirm the furnace fuse hasn’t tripped. Try resetting the fuse if it’s in the “off” position. If it immediately turns off after a subsequent reset, don’t try to reset it again and contact us at 208-578-4258.
  2. A single light is solid and the other is flickering slowly. This signifies the flame rollout switch is may be not working right. The component is a critical safety guard that helps in avoiding fires and carbon monoxide. You shouldn’t seek to take care of this problem yourself.
  3. An individual light is flickering fast and the other is flickering slowly. This typically indicates power polarity has been reversed. Your heater may have a wiring problem that calls for expert help from Age Heating & Cooling.
  4. The pair of lights are flashing slowly. This means your furnace’s blower motor probably isn’t operating. This piece sends warm air from the heater into your rooms. We can assist in determining what’s wrong with this piece.
  5. A single light is flickering slowly and the other is flickering fast. This means your heating system might have insufficient voltage or a short circuit. Call our specialists at 208-578-4258 for assistance.
  6. One light is flashing on, on and off while the other blinks on, off, on. This means there could be an issue with your heating system’s control board or wiring. Age Heating & Cooling can locate the problem and fix it.
  7. Both lights show every other slow blinks. This signifies your HVAC system likely has a flame issue. There could be trouble with its gas supply, gas valve or ignitor control. Contact us at 208-578-4258 for help.
  8. A single light flickers slowly while the other stays solid. This usually indicates your furnace’s limit switch is not working. The switch stops your furnace from getting too hot. Call the experts at Age Heating & Cooling for help.

Heating System Blower Operates But No Heat

Here’s what could be wrong when you hear your heating system’s blower fan running, but you aren’t receiving any heated air.

  • The duo of lights are showing alternating fast flickers. This means your furnace ignitor could be broken. This component lights gas in your heating system to make warm air and should be serviced by a specialist from Age Heating & Cooling.

Depend on Us for Professional Furnace Repair

When you have to have your HVAC equipment fixed fast, trust the professionals at Age Heating & Cooling. Our pros will take care of the issue promptly and have your house feeling cozy again soon. Contact us at 208-578-4258 or contact us online to schedule an appointment right away.