Furnace troubleshooting

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

While your Lennox® heating system can’t talk to you, it has a procedure to tell you about a furnace error.

Its control board has a set of LED lights that can share a fault code. Based on the issue, your heater might display continuous or flashing lights.

While there are various elementary heating fixes you can complete without an expert, many repairs are best left to HVAC technicians. When your heating system will not kick on or put out heat, reach out to Willco Air Conditioning, Refrigeration & Heating Inc. at 862-345-6896 for skilled furnace repair in Branchville.

Our specialists will rapidly identify and fix the breakdown, even if you don’t use a Lennox heater. We can fix any types or configuration—and get the heat returned to your residence without delay.


What Does the Flashing Light on My Heating System Mean?

Your heater relies on lights to flash code when it needs to be repaired. It also engages this system to tell you it’s heating properly.

Normal function consists of:

  • Concurrent slow flash—furnace working correctly.
  • Both lights flash fast—heater is initiating the call for heat.

If you notice one light going on and off slowly and the other going on and off rapidly, your heater could be having a low flame signal. This can occur even when your heating system is heating like it should. It means the flame sensing rod could be dirty or in the bad area on the burner. Reach out to us at 862-345-6896 for help.

Here are several other of the most routine problems for Lennox furnaces.

Heater Won’t Start

Here are a few of the light patterns you could see when your furnace refuses to or keep operating. The bulk of these problems must be handled by a technician, like one from Willco Air Conditioning, Refrigeration & Heating Inc..

  1. The duo of LED lights aren’t lit. This indicates your heater might not have electricity. Examine the breaker box to make sure the furnace fuse hasn’t flipped. Attempt to reset the fuse if it’s in the “off” area. If it rapidly turns off after you reset it, don’t try to reset it again and call us at 862-345-6896.
  2. A single light is stable and the other is flashing slowly. This shows the flame rollout switch is likely not working right. The component is a critical safety device that assists in stopping fires and carbon monoxide. You shouldn’t attempt to fix this malfunction without professional help.
  3. A single light is flickering quickly and the other is blinking slowly. This often indicates power polarity has been reversed. Your heater might have a wiring issue that needs specialized support from Willco Air Conditioning, Refrigeration & Heating Inc..
  4. All lights are flashing slowly. This signifies your heater’s blower motor probably isn’t working. This component circulates heated air from the heating system into your house. We can aid in pinpointing what’s causing a problem with this piece.
  5. An individual light is blinking slowly and the other is flashing quickly. This indicates your heating system might have insufficient voltage or a short circuit. Contact our professionals at 862-345-6896 for assistance.
  6. One light is blinking on, on and off while the other flickers on, off, on. This indicates there might be an error with your heater’s motherboard or wiring. Willco Air Conditioning, Refrigeration & Heating Inc. can find the issue and take care of it.
  7. The pair of lights are using alternating slow blinks. This indicates your heating system may have a flame failure. There might be an issue with its gas supply, gas valve or ignitor control. Reach out to us at 862-345-6896 for support.
  8. An individual light flashes slowly while the other is solid. This typically means your HVAC system’s limit switch is not working. The switch prevents your HVAC system from overheating. Call the specialists at Willco Air Conditioning, Refrigeration & Heating Inc. for help.

Furnace Blower Operates But No Warmth

Here’s what might be at fault when you observe your heating system’s blower fan on, but you aren’t receiving any heated air.

  • The pair of lights are showing alternating fast flashes. This means your furnace ignitor may be broken. This part kindles energy in your HVAC equipment to make warm air and should be fixed by a technician from Willco Air Conditioning, Refrigeration & Heating Inc..

Turn to Us for Professional Furnace Repair

When you have to get your HVAC equipment repaired without delay, depend on the experts at Willco Air Conditioning, Refrigeration & Heating Inc.. Our techs will take care of the error without delay and have your home feeling comfortable again in no time. Call us at 862-345-6896 or contact us online to schedule an appointment today.

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