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 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 problem, your furnace might use steady or flashing lights.

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

Our specialists will speedily diagnose and take care of the issue, even if you don’t own a Lennox heating system. We can service all kinds or configuration—and get the warmth returned to your residence quickly.


What Does the Flashing Light on My Furnace Mean?

Your heating system depends on lights to flash code when it requires repairs. It also works these lights to let you know it’s heating properly.

Normal heating involves:

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

If you realize that a solitary light blinking slowly and the other flashing rapidly, 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. Reach out to us at 815-410-1128 for assistance.

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

Heater Won’t Kick On

Here are many of the light patterns you may notice when your heat refuses to or keep heating. The bulk of these problems have to be fixed 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. Check the breaker box to confirm the heating system fuse isn’t triggered. You should reset the fuse if it is in the “off” spot. If it instantly trips after a subsequent reset, don’t try to reset it again and get in touch with us us at 815-410-1128.
  2. An individual 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. An individual light is blinking rapidly and the other is flickering slowly. This often means power polarity has been transposed. Your heating system might have a wiring issue that needs expert support from Jett's Heating & Air Inc..
  4. The duo of lights are flashing slowly. This signifies your heating system’s blower motor possibly isn’t operating. This component distributes hot air from the heating system into your rooms. We can help in pinpointing what’s causing an issue with this piece.
  5. An individual light is flashing slowly and the other is flashing rapidly. This indicates 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 blinking on, on and off while the other flashes on, off, on. This means there may be trouble with your furnace’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 signifies your heating system may have a flame failure. There might be an issue with its gas supply, gas valve or ignitor control. Call us at 815-410-1128 for support.
  8. A single light flashes slowly while the other stays 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 experts at Jett's Heating & Air Inc. for assistance.

Heating System Blower Runs But No Heat

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

  • The pair of lights display every other quick flickers. This means your furnace ignitor may be broken. This piece kindles gas in your heating system to create warm air and should be repaired by a technician from Jett's Heating & Air Inc..

Depend on Us for Expert Furnace Repair

When you have to have your heating system fixed fast, turn to the technicians at Jett's Heating & Air Inc.. Our pros will repair the problem promptly and have your house feeling cozy again in no time. Call us at 815-410-1128 or contact us online to schedule an appointment right away.

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