Furnace troubleshooting

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

While your Lennox® furnace can’t talk to you, it does have a way to get your attention when there’s a furnace error.

Its motherboard has double LED lights that can share a fault code. Depending on the failure, your heater might show solid or flashing lights.

Though there are various basic furnace adjustments you can complete without an expert, the majority of tasks are best taken care of by the professionals. When your furnace won’t turn on or provide warm air, get in touch with Forster Heating at 530-885-8081 for experienced furnace repair in Auburn.

Our experts will speedily diagnose and take care of the breakdown, even if you don’t have a Lennox heating system. We can service any kinds or configuration—and get the warmth returned to your home fast.


What Does the Blinking Light on My Heater Mean?

Your furnace uses lights to flash code when it requires repairs. It also works this setup to relay it’s heating like it should.

Regular operation involves:

  • Concurrent slow flash—furnace running correctly.
  • Simultaneous fast flash—heating system is starting to call for heat.

If you realize that a single light blinking slowly and the other going on and off rapidly, your heating system may be experiencing a low flame signal. This can happen even when your heater is running properly. It means the flame sensing rod might need to be cleaned or in the incorrect spot on the burner. Call us at 530-885-8081 for support.

Here are some of the most routine faults for Lennox heaters.

Heating System Will Not Turn On

Here are a few of the light arrangements you may see when your heat will not or stay on. The majority of these problems need to be taken care of by an expert, for instance from Forster Heating.

  1. The duo of LED lights are extinguished. This signifies your heating system might not have power. Find the breaker box to make sure the heater fuse hasn’t triggered. Try resetting the fuse if it has moved into the “off” spot. If it immediately trips following a reset, leave the breaker alone and call us at 530-885-8081.
  2. One light is solid and the other is blinking slowly. This means the flame rollout switch is likely not working right. The component is a critical safety guard that assists in stopping fires and carbon monoxide. You shouldn’t try to repair this issue yourself.
  3. One light is flickering rapidly and the other is blinking slowly. This likely signifies power polarity has been inverted. Your heating system might have a wiring fault that requires specialized support from Forster Heating.
  4. Both lights are blinking slowly. This means your heater’s blower motor possibly isn’t running. This part distributes hot air from the heating system into your rooms. We can assist in figuring out what’s wrong with this piece.
  5. One light is flickering slowly and the other is blinking fast. This indicates your HVAC system may have low voltage or a short circuit. Contact our experts at 530-885-8081 for assistance.
  6. One light is flickering on, on and off while the other flashes on, off, on. This signifies there may be a malfunction with your heater’s control panel or wiring. Forster Heating can determine the fault and handle it.
  7. The pair of lights show alternating slow flashes. This means your heater possibly has a flame error. There might be a problem with its gas supply, gas valve or ignitor control. Get in touch with us at 530-885-8081 for assistance.
  8. One light flickers slowly while the other is steady. This often means your heating system’s limit switch is open. The switch prevents your heating system from getting too hot. Reach out to the specialists at Forster Heating for support.

Furnace Blower Operates But No Warm Air

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

  • Both lights display alternating rapid flickers. This indicates your furnace ignitor might be broken. This piece ignites energy in your HVAC equipment to produce warm air and should be serviced by a technician from Forster Heating.

Depend on Us for Professional Furnace Repair

When you have to get your heating system in working order fast, depend on the specialists at Forster Heating. Our techs will repair the error promptly and have your home feeling comfortable again soon. Get in touch with us at 530-885-8081 or contact us online to schedule an appointment right away.

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