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

December 06, 2019

While your Lennox® heater can’t talk to you, it does have a way to tell you about a furnace error.

Its control board has a set of LED lights that can display a fault code. Subject to the problem, your furnace may display solid or flashing lights.

Though there are various basic heating fixes you can complete yourself, most repairs are best taken care of by the professionals. When your heating system won’t start or deliver warm air, call LTS Plumbing & Heating Inc. at 570-648-0748 for professional furnace repair in Paxinos.

Our experts will quickly determine and repair the malfunction, even if you don’t have a Lennox furnace. We can fix any types or models—and get the warmth returned to your house without delay.


What Does the Flashing Light on My Heating System Mean?

Your furnace relies on lights to flash code when it isn’t working right. It also engages this setup to relay it’s operating properly.

Regular function involves:

  • Simultaneous slow flash—heater heating like it should.
  • Simultaneous fast flash—heater is starting to call for heat.

If you realize that a solitary light blinking slowly and the other blinking quickly, your heater might have a low flame signal. This can happen even when your furnace is operating correctly. It indicates the flame sensing rod might need to be cleaned or in the incorrect area on the burner. Reach out to us at 570-648-0748 for support.

Here are some of the most typical errors for Lennox HVAC systems.

Furnace Won’t Kick On

Here are a few of the light patterns you might see when your furnace won’t turn on or keep heating. The bulk of these issues have to be taken care of by an expert, for instance from LTS Plumbing & Heating Inc..

  1. The pair of LED lights are off. This means your heating system might not be receiving power. Find the breaker box to ensure the heater fuse has not triggered. Try resetting the fuse if it’s in the “off” spot. If it rapidly trips after a subsequent reset, leave the breaker alone and get in touch with us us at 570-648-0748.
  2. One light is continuous and the other is blinking slowly. This signifies the flame rollout switch is may be malfunctioning. The switch is a critical safety guard that assists in preventing fires and carbon monoxide. You shouldn’t attempt to fix this fault on your own.
  3. An individual light is flickering rapidly and the other is flashing slowly. This often indicates power polarity has been inverted. Your heater might have a wiring fault that requires specialized help from LTS Plumbing & Heating Inc..
  4. The duo of lights are flickering slowly. This signifies your furnace’s blower motor probably isn’t operating. This component moves warm air from the furnace into your house. We can aid in pinpointing what’s wrong with this piece.
  5. An individual light is blinking slowly and the other is flickering quickly. This means your heater could have not enough voltage or a short circuit. Reach out to our specialists at 570-648-0748 for support.
  6. One light is blinking on, on and off while the other flickers on, off, on. This signifies there could be trouble with your heating system’s control panel or wiring. LTS Plumbing & Heating Inc. can pinpoint the error and handle it.
  7. Both lights are using alternating slow flashes. This means your HVAC system possibly has a flame issue. There might be trouble with its gas supply, gas valve or ignitor control. Reach out to us at 570-648-0748 for help.
  8. One light flickers slowly while the other is solid. This typically indicates your heater’s limit switch is open. The switch stops your HVAC system from getting too hot. Reach out to the experts at LTS Plumbing & Heating Inc. for assistance.

Heating System Blower Runs But No Heat

Here’s what might be broken when you notice your heating system’s blower fan running, but you aren’t receiving any heat.

  • Both lights are showing alternate quick flickers. This signifies your furnace ignitor could not be working. This component lights energy in your furnace to produce heat and should be serviced by a specialist from LTS Plumbing & Heating Inc..

Turn to Us for Expert Furnace Repair

When you have to get your furnace in working order fast, trust the professionals at LTS Plumbing & Heating Inc.. Our technicians will repair the problem right away and have your rooms feeling cozy again in a short time. Contact us at 570-648-0748 or contact us online to request an appointment now.