Furnace troubleshooting

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

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

Its control board has twin LED lights that can show a fault code. Depending on the problem, your heating system might display continuous or flashing lights.

Though there are various simple furnace repairs you can complete yourself, many repairs are best taken care of by HVAC technicians. When your furnace will not kick on or deliver warmth, reach out to Dial One Mears Air Conditioning & Heating Inc at 602-832-7808 for experienced furnace repair in Phoenix.

Our experts will quickly identify and fix the breakdown, even if you don’t own a Lennox heating system. We can repair all types or makes—and get the heat restored to your house without delay.


What Does the Blinking Light on My Heating System Mean?

Your heating system uses lights to flash code when it needs to be repaired. It also engages this system to let you know it’s heating like it should.

Regular function consists of:

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

If you realize that a solitary light going on and off slowly and the other flashing fast, your heating system might be having a low flame signal. This can take place even when your heater is working properly. It signifies the flame sensing rod might have build-up or in the incorrect location on the burner. Reach out to us at 602-832-7808 for support.

Here are some of the most typical problems for Lennox heating systems.

Furnace Won’t Kick On

Here are a few of the light sequences you might notice when your heat refuses to or keep running. Most of these errors have to be fixed by a professional, such as one from Dial One Mears Air Conditioning & Heating Inc.

  1. The duo of LED lights are extinguished. This indicates your furnace might not be receiving power. Look at the breaker box to make sure the heater fuse is not triggered. You should reset the fuse if it’s in the “off” spot. If it promptly turns off after you reset it, don’t touch the breaker and call us at 602-832-7808.
  2. A single light is continuous and the other is blinking slowly. This implies the flame rollout switch is may be not working right. The component is an important safety tool that assists in avoiding fires and carbon monoxide. You shouldn’t seek to take care of this problem without professional help.
  3. One light is flashing quickly and the other is flashing slowly. This usually indicates power polarity has been inverted. Your heating system may have a wiring issue that requires professional help from Dial One Mears Air Conditioning & Heating Inc.
  4. The pair of lights are blinking slowly. This signifies your furnace’s blower motor likely isn’t working. This piece circulates heated air from the heating system into your space. We can aid in determining what’s causing an issue with this piece.
  5. A single light is blinking slowly and the other is flickering fast. This signifies your heater might have not enough voltage or a short circuit. Call our technicians at 602-832-7808 for help.
  6. One light is flickering on, on and off while the other flashes on, off, on. This indicates there might be a problem with your furnace’s control panel or wiring. Dial One Mears Air Conditioning & Heating Inc can pinpoint the fault and repair it.
  7. The duo of lights display every other slow blinks. This indicates your HVAC system may have a flame problem. There could be a problem with its gas supply, gas valve or ignitor control. Contact us at 602-832-7808 for assistance.
  8. A single light flashes slowly while the other is continuous. This often signifies your furnace’s limit switch is open. The switch stops your heater from overheating. Contact the pros at Dial One Mears Air Conditioning & Heating Inc for help.

Furnace Blower Runs But No Warmth

Here’s what might be broken when you hear your furnace’s blower fan on, but you aren’t getting any warmth.

  • The duo of lights are showing alternating fast flashes. This signifies your furnace ignitor could not be in working order. This part kindles gas in your furnace to make warmth and should be serviced by a technician from Dial One Mears Air Conditioning & Heating Inc.

Depend on Us for Expert Furnace Repair

When you have to have your heating system repaired without delay, turn to the experts at Dial One Mears Air Conditioning & Heating Inc. Our technicians will handle the fault quickly and have your home feeling cozy again in a short time. Contact us at 602-832-7808 or contact us online to schedule an appointment now.

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