Furnace troubleshooting

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

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

Its control board has double LED lights that can show a fault code. Based on the malfunction, your furnace could use solid or flashing lights.

Although there are some simple furnace repairs you can take care of without an expert, many fixes are best handled by the professionals. When your heater will not turn on or put out heat, reach out to All Weather Heating & Air Conditioning Inc at 256-801-4701 for expert furnace repair in Huntsville.

Our specialists will quickly detect and repair the issue, even if you don’t use a Lennox furnace. We can service whichever brands or configuration—and get the heat returned to your residence fast.


What Does the Blinking Light on My Furnace Mean?

Your heating system relies on lights to flash code when it requires repairs. It also engages these lights to let you know it’s running like it should.

Normal heating involves:

  • Both lights flash slowly—heating system working correctly.
  • Concurrent fast flash—heater is initiating the call for heat.

If you notice one light flashing slowly and the other blinking rapidly, your heater might be having a low flame signal. This can occur even when your furnace is running correctly. It signifies the flame sensing rod might need to be cleaned or in the incorrect spot on the burner. Call us at 256-801-4701 for help.

Here are several other of the most routine problems for Lennox heaters.

Heating System Refuses to Start

Here are many of the light arrangements you may notice when your heating system will not or keep heating. The bulk of these issues have to be fixed by a specialist, such as one from All Weather Heating & Air Conditioning Inc.

  1. The pair of LED lights are extinguished. This indicates your heating system might not have electricity. Check the breaker box to make sure the heater fuse is not triggered. Attempt to reset the fuse if it is in the “off” position. If it promptly flips after a subsequent reset, don’t touch the breaker and call us at 256-801-4701.
  2. A single light is stable and the other is flickering slowly. This signifies the flame rollout switch is probably malfunctioning. The part is an important safety device that aids in avoiding fires and carbon monoxide. You shouldn’t try to fix this issue yourself.
  3. One light is flickering fast and the other is flickering slowly. This likely means power polarity has been inverted. Your heater might have a wiring issue that needs professional support from All Weather Heating & Air Conditioning Inc.
  4. The pair of lights are flashing slowly. This indicates your heater’s blower motor possibly isn’t operating. This part circulates hot air from the heater into your house. We can aid in figuring out what’s causing a problem with this piece.
  5. A single light is flashing slowly and the other is blinking quickly. This indicates your heating system might have insufficient voltage or a short circuit. Call our technicians at 256-801-4701 for help.
  6. One light is flickering on, on and off while the other flashes on, off, on. This means there could be a problem with your furnace’s control board or wiring. All Weather Heating & Air Conditioning Inc can find the issue and fix it.
  7. The pair of lights display alternating slow blinks. This indicates your furnace possibly has a flame problem. There could be trouble with its gas supply, gas valve or ignitor control. Get in touch with us at 256-801-4701 for support.
  8. A single light flickers slowly while the other remains solid. This typically means your furnace’s limit switch is malfunctioning. The switch stops your HVAC system from getting too hot. Call the experts at All Weather Heating & Air Conditioning Inc for assistance.

Furnace Blower Runs But No Warmth

Here’s what could be at fault when you observe your heater’s blower fan on, but you aren’t gaining any warmth.

  • Both lights display alternating fast flickers. This means your furnace ignitor could be broken. This part ignites energy in your furnace to produce warm air and should be serviced by an expert from All Weather Heating & Air Conditioning Inc.

Turn to Us for Expert Furnace Repair

When you need to have your heater repaired fast, depend on the experts at All Weather Heating & Air Conditioning Inc. Our technicians will handle the fault quickly and have your home feeling comfortable again soon. Reach out to us at 256-801-4701 or contact us online to request an appointment right away.

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