Furnace troubleshooting

Top Lennox® Furnace Error Codes (and What They Mean)

While your Lennox® furnace cannot speak to you, it has a way to get your attention when there’s a furnace error.

Its control panel has a set of LED lights that can share a fault code. Subject to the problem, your furnace might use continuous or flashing lights.

While there are various simple heating fixes you can take care of yourself, most repairs are best taken care of by experts. When your furnace won’t turn on or give warmth, contact Stieferman Heating Company Inc at 573-203-3908 for skilled furnace repair in Jefferson City.

Our experts will rapidly identify and repair the breakdown, even if you don’t have a Lennox furnace. We can service whichever kinds or makes—and get the heat reintroduced to your residence quickly.


What Does the Flashing Light on My Furnace Mean?

Your furnace depends on lights to flash code when it needs to be repaired. It also engages this setup to let you know it’s running like it should.

Correct heating involves:

  • Simultaneous slow flash—heating system operating like it should.
  • Concurrent fast flash—furnace is beginning to call for heat.

If you notice a single light going on and off slowly and the other blinking fast, your furnace could be experiencing a low flame signal. This can take place even when your heating system is working correctly. It indicates the flame sensing rod could be dirty or in the incorrect location on the burner. Reach out to us at 573-203-3908 for support.

Here are a few other of the most typical issues for Lennox HVAC systems.

Heater Refuses to Kick On

Here are a few of the light sequences you could see when your heating system will not or keep heating. Most of these problems must be repaired by an expert, such as one from Stieferman Heating Company Inc.

  1. The duo of LED lights aren’t lit. This indicates your heating system might not have power. Go to the breaker box to confirm the furnace fuse isn’t flipped. Try resetting the fuse if it’s in the “off” area. If it instantly turns off after a subsequent reset, leave the breaker alone and call us at 573-203-3908.
  2. A single light is solid and the other is blinking slowly. This signifies the flame rollout switch is probably not working right. The part is an important safety guard that aids in stopping fires and carbon monoxide. You shouldn’t try to handle this problem yourself.
  3. A single light is flashing quickly and the other is flashing slowly. This typically means power polarity has been inverted. Your furnace might have a wiring issue that requires specialized aid from Stieferman Heating Company Inc.
  4. The pair of lights are flickering slowly. This means your furnace’s blower motor possibly isn’t operating. This piece moves warm air from the heating system into your space. We can aid in pinpointing what’s causing an issue with this component.
  5. One light is flickering slowly and the other is flashing rapidly. This means your heating system might have low voltage or a short circuit. Reach out to our technicians at 573-203-3908 for assistance.
  6. One light is blinking on, on and off while the other flashes on, off, on. This means there may be a malfunction with your heating system’s control panel or wiring. Stieferman Heating Company Inc can locate the error and take care of it.
  7. The pair of lights display every other slow blinks. This indicates your heating system possibly has a flame error. There could be a problem with its gas supply, gas valve or ignitor control. Reach out to us at 573-203-3908 for assistance.
  8. A single light flashes slowly while the other stays solid. This usually means your furnace’s limit switch is malfunctioning. The switch prevents your furnace from getting too hot. Call the professionals at Stieferman Heating Company Inc for help.

Furnace Blower Runs But No Warmth

Here’s what might be wrong when you hear your heater’s blower fan on, but you aren’t getting any heat.

  • Both lights are showing alternating rapid flickers. This indicates your furnace ignitor might not be working. This piece lights fuel in your heating system to produce warm air and should be repaired by a professional from Stieferman Heating Company Inc.

Depend on Us for Professional Furnace Repair

When you have to have your HVAC equipment repaired without delay, trust the experts at Stieferman Heating Company Inc. Our pros will handle the issue promptly and have your space feeling relaxing again soon. Reach out to us at 573-203-3908 or contact us online to schedule an appointment right away.

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