Furnace troubleshooting

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

While your Lennox® furnace cannot chat with you, it possesses a method to communicate a furnace error.

Its control board has double LED lights that can display a fault code. Subject to the malfunction, your furnace could use solid or flashing lights.

Though there are some elementary HVAC fixes you can finish yourself, many services are best taken care of by HVAC technicians. When your heating system refuses to kick on or put out warm air, contact Jett's Heating & Air Inc. at 815-410-1128 for experienced furnace repair in McHenry.

Our experts will speedily pinpoint and take care of the issue, even if you don’t own a Lennox heater. We can repair all types or configuration—and get the warmth reintroduced to your house without delay.


What Does the Flashing Light on My Furnace Mean?

Your heater depends on lights to flash code when it requires repairs. It also works these lights to relay it’s heating properly.

Normal heating involves:

  • Simultaneous slow flash—furnace operating correctly.
  • Simultaneous fast flash—heating system is initiating the call for heat.

If you realize that a solitary light blinking slowly and the other flashing fast, your furnace could be having a low flame signal. This can happen even when your furnace is running like it should. It means the flame sensing rod could be dirty or in the bad area on the burner. Contact us at 815-410-1128 for assistance.

Here are several other of the most common faults for Lennox furnaces.

Heating System Won’t Start

Here are many of the light patterns you may observe when your heater refuses to or stay on. The bulk of these problems have to be handled by an expert, for instance from Jett's Heating & Air Inc..

  1. Both LED lights are off. This signifies your heater might not have power. Find the breaker box to confirm the heater fuse isn’t flipped. You should reset the fuse if it is in the “off” area. If it instantly trips after a subsequent reset, don’t touch the breaker and get in touch with us us at 815-410-1128.
  2. A single light is continuous and the other is blinking slowly. This signifies the flame rollout switch is may be open. The switch is a critical safety mechanism that helps in avoiding fires and carbon monoxide. You shouldn’t seek to repair this issue yourself.
  3. A single light is blinking rapidly and the other is flickering slowly. This often means power polarity has been transposed. Your heater could have a wiring issue that needs specialized help from Jett's Heating & Air Inc..
  4. The duo of lights are flashing slowly. This signifies your heater’s blower motor likely isn’t operating. This component distributes hot air from the heating system into your rooms. We can help in figuring out what’s causing a problem with this piece.
  5. An individual light is flashing slowly and the other is flashing fast. This signifies your furnace might have low voltage or a short circuit. Get in touch with our technicians at 815-410-1128 for help.
  6. One light is flickering on, on and off while the other flashes on, off, on. This means there may be trouble with your HVAC system’s motherboard or wiring. Jett's Heating & Air Inc. can locate the error and handle it.
  7. The pair of lights are using alternating slow flashes. This indicates your heater may have a flame failure. There may be trouble with its gas supply, gas valve or ignitor control. Call us at 815-410-1128 for assistance.
  8. A single light flashes slowly while the other remains continuous. This typically means your heating system’s limit switch is not working. The switch keeps your heating system from becoming too warm. Call the professionals at Jett's Heating & Air Inc. for assistance.

Heating System Blower Runs But No Heat

Here’s what may be at fault when you hear your heater’s blower fan running, but you aren’t getting any warm air.

  • The duo of lights display every other rapid flickers. This means your furnace ignitor may not be working. This component kindles fuel in your furnace to create warmth and should be fixed by a technician from Jett's Heating & Air Inc..

Depend on Us for Expert Furnace Repair

When you have to have your furnace fixed fast, turn to the technicians at Jett's Heating & Air Inc.. Our pros will repair the error promptly and have your residence feeling relaxing again in no time. Call us at 815-410-1128 or contact us online to schedule an appointment now.

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