Furnace troubleshooting

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

While your Lennox® heating system isn’t able to talk to you, it has a way to communicate a furnace error.

Its control panel has two LED lights that can share a fault code. Subject to the issue, your furnace could use solid or flashing lights.

While there are certain elementary HVAC repairs you can take care of without an expert, most tasks are best left to the professionals. When your heating system will not kick on or deliver heated air, contact Rapids Sheet Metal Works Inc at 715-301-0256 for expert furnace repair in Wisconsin Rapids.

Our specialists will quickly identify and repair the failure, even if you don’t have a Lennox heater. We can repair any types or configuration—and get the comfort restored to your home without delay.


What Does the Flickering Light on My Furnace Mean?

Your heating system depends on lights to flash code when it needs to be repaired. It also works these lights to tell you it’s heating like it should.

Normal operation consists of:

  • Both lights flash slowly—heating system running properly.
  • Both lights flash fast—heating system is starting to call for heat.

If you realize that a lone light going on and off slowly and the other going on and off rapidly, your heating system may have a low flame signal. This can occur even when your heating system is operating properly. It signifies the flame sensing rod may need to be cleaned or in the bad spot on the burner. Call us at 715-301-0256 for assistance.

Here are several other of the most common errors for Lennox HVAC systems.

Heating System Won’t Kick On

Here are some of the light sequences you might notice when your heat won’t turn on or keep heating. The majority of these issues have to be taken care of by a professional, for instance from Rapids Sheet Metal Works Inc.

  1. The pair of LED lights are extinguished. This means your HVAC system might not have power. Find the breaker box to ensure the heating system fuse isn’t flipped. Attempt to reset the fuse if it’s in the “off” spot. If it promptly flips after you reset it, don’t touch the breaker and get in touch with us us at 715-301-0256.
  2. One light is stable and the other is flashing slowly. This signifies the flame rollout switch is likely open. The switch is an important safety tool that aids in preventing fires and carbon monoxide. You shouldn’t try to take care of this malfunction on your own.
  3. An individual light is blinking rapidly and the other is blinking slowly. This often indicates power polarity has been inverted. Your heater may have a wiring error that needs specialized aid from Rapids Sheet Metal Works Inc.
  4. Both lights are flickering slowly. This means your heating system’s blower motor probably isn’t running. This piece circulates heated air from the HVAC system into your residence. We can help in figuring out what’s wrong with this piece.
  5. A single light is flashing slowly and the other is flickering rapidly. This indicates your HVAC system might have not enough voltage or a short circuit. Reach out to our technicians at 715-301-0256 for assistance.
  6. One light is flashing on, on and off while the other blinks on, off, on. This signifies there could be a malfunction with your furnace’s control board or wiring. Rapids Sheet Metal Works Inc can locate the error and fix it.
  7. The duo of lights are using alternate slow blinks. This means your furnace may have a flame error. There could be trouble with its gas supply, gas valve or ignitor control. Contact us at 715-301-0256 for support.
  8. A single light flashes slowly while the other is continuous. This usually means your furnace’s limit switch is not working. The switch stops your heating system from getting too hot. Call the professionals at Rapids Sheet Metal Works Inc for help.

Furnace Blower Runs But No Heat

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

  • The pair of lights display every other fast flickers. This signifies your furnace ignitor may not be working. This part ignites gas in your furnace to make heat and should be repaired by a professional from Rapids Sheet Metal Works Inc.

Turn to Us for Expert Furnace Repair

When you have to get your heating system fixed quickly, turn to the technicians at Rapids Sheet Metal Works Inc. Our technicians will take care of the fault right away and have your home feeling comfortable again in no time. Get in touch with us at 715-301-0256 or contact us online to schedule an appointment right away.

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