Furnace troubleshooting

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

While your Lennox® HVAC equipment can’t talk to you, it possesses a method to communicate a furnace error.

Its control panel has two LED lights that can share a fault code. Subject to the failure, your furnace may display continuous or flashing lights.

Although there are some basic HVAC fixes you can take care of yourself, most tasks are best taken care of by experts. When your furnace will not turn on or put out heat, reach out to M & S Heating & Air LLC at 301-363-4699 for experienced furnace repair in Mechanicsville.

Our technicians will speedily spot and handle the issue, even if you don’t have a Lennox heating system. We can service any types or makes—and get the comfort restored to your home quickly.


What Does the Flickering Light on My Heater Mean?

Your heating system uses lights to flash code when it requires repairs. It also works this setup to tell you it’s heating correctly.

Regular operation consists of:

  • Both lights flash slowly—furnace working correctly.
  • Concurrent fast flash—heater is starting to call for heat.

If you see a lone light flashing slowly and the other going on and off fast, your heater might be having a low flame signal. This can take place even when your heater is working like it should. It signifies the flame sensing rod may need to be cleaned or in the incorrect location on the burner. Call us at 301-363-4699 for assistance.

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

Heating System Won’t Start

Here are a few of the light patterns you might notice when your heating system will not or keep running. The majority of these problems need to be fixed by an expert, such as one from M & S Heating & Air LLC.

  1. Both LED lights are extinguished. This means your heating system might not have electricity. Check the breaker box to ensure the heater fuse isn’t triggered. Attempt to reset the fuse if it has moved into the “off” spot. If it promptly trips after you reset it, don’t try to reset it again and get in touch with us us at 301-363-4699.
  2. One light is solid and the other is flickering slowly. This means the flame rollout switch is may be malfunctioning. The part is an important safety tool that aids in avoiding fires and carbon monoxide. You shouldn’t seek to take care of this malfunction yourself.
  3. A single light is flashing fast and the other is flashing slowly. This typically signifies power polarity has been transposed. Your heater might have a wiring problem that calls for specialized assistance from M & S Heating & Air LLC.
  4. The pair of lights are flickering slowly. This indicates your heater’s blower motor probably isn’t working. This component distributes heated air from the furnace into your space. We can aid in pinpointing what’s wrong with this piece.
  5. One light is flashing slowly and the other is flickering rapidly. This means your furnace might have insufficient voltage or a short circuit. Reach out to our professionals at 301-363-4699 for assistance.
  6. One light is flashing on, on and off while the other flashes on, off, on. This signifies there may be trouble with your furnace’s control board or wiring. M & S Heating & Air LLC can locate the error and handle it.
  7. The pair of lights are using every other slow flickers. This indicates your HVAC equipment possibly has a flame failure. There could be trouble with its gas supply, gas valve or ignitor control. Call us at 301-363-4699 for support.
  8. An individual light blinks slowly while the other stays continuous. This typically signifies your heating system’s limit switch is open. The switch stops your heater from getting too hot. Contact the pros at M & S Heating & Air LLC for assistance.

Heater Blower Operates But No Warmth

Here’s what could be wrong when you observe your heating system’s blower fan on, but you aren’t receiving any warm air.

  • The duo of lights display alternate rapid flickers. This indicates your furnace ignitor might be broken. This part kindles gas in your heating system to make heat and should be fixed by a professional from M & S Heating & Air LLC.

Depend on Us for Professional Furnace Repair

When you need to get your heating system repaired without delay, depend on the specialists at M & S Heating & Air LLC. Our pros will take care of the problem promptly and have your residence feeling relaxing again in a short time. Call us at 301-363-4699 or contact us online to get an appointment now.

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