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

December 06, 2019

While your Lennox® HVAC equipment can’t speak to you, it does have a process to tell you about a furnace error.

Its motherboard has twin LED lights that can share a fault code. Depending on the failure, your furnace may display steady or flashing lights.

While there are certain basic HVAC repairs you can take care of on your own, most tasks are best handled by the professionals. When your heater refuses to start or give warmth, get in touch with Kohles & Bach Heating & Cooling at 515-207-6569 for skilled furnace repair in Des Moines.

Our specialists will rapidly identify and fix the fault, even if you don’t have a Lennox heater. We can service whichever kinds or models—and get the heat restored to your home without delay.


What Does the Flickering Light on My Heating System Mean?

Your furnace relies on lights to flash code when it isn’t working right. It also uses this system to tell you it’s working like it should.

Regular function involves:

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

If you realize that a solitary light blinking slowly and the other blinking rapidly, your heating system may have a low flame signal. This can occur even when your heater is operating correctly. It means the flame sensing rod might be dirty or in the bad location on the burner. Call us at 515-207-6569 for assistance.

Here are a few other of the most routine errors for Lennox heaters.

Heater Will Not Turn On

Here are some of the light patterns you could observe when your heating system refuses to or keep operating. Most of these errors must be taken care of by a professional, like one from Kohles & Bach Heating & Cooling.

  1. The duo of LED lights are extinguished. This signifies your heater might not be receiving power. Examine the breaker box to make sure the furnace fuse hasn’t triggered. You should reset the fuse if it is in the “off” spot. If it promptly trips after you reset it, leave the breaker alone and get in touch with us us at 515-207-6569.
  2. A single light is continuous and the other is flashing slowly. This shows the flame rollout switch is may be malfunctioning. The switch is an essential safety tool that helps in preventing fires and carbon monoxide. You shouldn’t seek to handle this problem without professional help.
  3. One light is flickering quickly and the other is flickering slowly. This often signifies power polarity has been transposed. Your furnace may have a wiring issue that requires professional help from Kohles & Bach Heating & Cooling.
  4. All lights are flickering slowly. This indicates your heater’s blower motor likely isn’t working. This part circulates hot air from the furnace into your home. We can assist in pinpointing what’s wrong with this piece.
  5. An individual light is blinking slowly and the other is flickering fast. This signifies your heating system might have not enough voltage or a short circuit. Reach out to our technicians at 515-207-6569 for assistance.
  6. One light is flashing on, on and off while the other flashes on, off, on. This indicates there might be a malfunction with your HVAC system’s control board or wiring. Kohles & Bach Heating & Cooling can find the problem and handle it.
  7. The pair of lights show alternate slow blinks. This indicates your furnace likely has a flame failure. There may be trouble with its gas supply, gas valve or ignitor control. Contact us at 515-207-6569 for help.
  8. A single light flashes slowly while the other stays steady. This typically signifies your heating system’s limit switch is not working. The switch stops your heater from overheating. Get in touch with the specialists at Kohles & Bach Heating & Cooling for assistance.

Heater Blower Works But No Heat

Here’s what may be broken when you observe your heating equipment’s blower fan running, but you aren’t gaining any heat.

  • The pair of lights display alternating quick flashes. This signifies your furnace ignitor might be broken. This piece kindles gas in your heating system to create heat and should be fixed by an expert from Kohles & Bach Heating & Cooling.

Turn to Us for Skilled Furnace Repair

When you have to have your furnace in working order quickly, turn to the experts at Kohles & Bach Heating & Cooling. Our techs will repair the problem right away and have your home feeling relaxing again soon. Call us at 515-207-6569 or contact us online to schedule an appointment now.