Furnace troubleshooting

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

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

Its control board has double LED lights that can display a fault code. Subject to the fault, your heating system could show steady or flashing lights.

Although there are certain elementary heating fixes you can do without an expert, many services are best left to the professionals. When your furnace refuses to kick on or deliver warmth, reach out to Toptec Heating, Cooling, Plumbing & Electrical at 847-362-0262 for experienced furnace repair in Libertyville.

Our specialists will swiftly detect and take care of the issue, even if you don’t use a Lennox heater. We can fix whichever types or configuration—and get the comfort reintroduced to your house without delay.


What Does the Flickering Light on My Furnace Mean?

Your furnace relies on lights to flash code when it requires repairs. It also works this system to let you know it’s operating properly.

Regular heating involves:

  • Both lights flash slowly—heater heating correctly.
  • Concurrent fast flash—heater is starting to call for heat.

If you notice a solitary light flashing slowly and the other blinking rapidly, your heating system might be having a low flame signal. This can happen even when your furnace is operating properly. It indicates the flame sensing rod might be dirty or in the bad area on the burner. Call us at 847-362-0262 for assistance.

Here are some of the most common faults for Lennox HVAC systems.

Furnace Will Not Start

Here are some of the light patterns you could see when your heating system refuses to or keep running. The majority of these errors need to be repaired by a specialist, such as one from Toptec Heating, Cooling, Plumbing & Electrical.

  1. Both LED lights are off. This signifies your HVAC system might not have power. Find the breaker box to confirm the furnace fuse isn’t tripped. Try resetting the fuse if it’s in the “off” position. If it promptly turns off after a subsequent reset, don’t touch the breaker and call us at 847-362-0262.
  2. A single light is solid and the other is flashing slowly. This shows the flame rollout switch is possibly malfunctioning. The part is a critical safety guard that helps in stopping fires and carbon monoxide. You shouldn’t seek to fix this problem on your own.
  3. An individual light is blinking rapidly and the other is flickering slowly. This often signifies power polarity has been inverted. Your furnace could have a wiring fault that calls for expert help from Toptec Heating, Cooling, Plumbing & Electrical.
  4. The pair of lights are flashing slowly. This means your furnace’s blower motor likely isn’t working. This part circulates heated air from the furnace into your rooms. We can assist in pinpointing what’s causing a problem with this piece.
  5. A single light is blinking slowly and the other is blinking fast. This indicates your heating system could have insufficient voltage or a short circuit. Get in touch with our professionals at 847-362-0262 for assistance.
  6. One light is blinking on, on and off while the other flickers on, off, on. This means there could be an issue with your heating system’s control panel or wiring. Toptec Heating, Cooling, Plumbing & Electrical can find the problem and take care of it.
  7. The pair of lights are using alternating slow flashes. This signifies your heating system possibly has a flame error. There could be an issue with its gas supply, gas valve or ignitor control. Reach out to us at 847-362-0262 for help.
  8. One light flickers slowly while the other is solid. This typically signifies your heating system’s limit switch is open. The switch keeps your heating system from overheating. Get in touch with the experts at Toptec Heating, Cooling, Plumbing & Electrical for assistance.

Heating System Blower Runs But No Heat

Here’s what may be at fault when you notice your heating equipment’s blower fan working, but you aren’t gaining any heat.

  • Both lights are showing alternate fast flashes. This indicates your furnace ignitor may not be working. This part kindles energy in your furnace to make heat and should be serviced by a professional from Toptec Heating, Cooling, Plumbing & Electrical.

Depend on Us for Professional Furnace Repair

When you need to have your heater fixed without delay, turn to the professionals at Toptec Heating, Cooling, Plumbing & Electrical. Our technicians will handle the fault promptly and have your residence feeling relaxing again in a short time. Get in touch with us at 847-362-0262 or contact us online to request an appointment right away.

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