Furnace troubleshooting

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

While your Lennox® furnace can’t speak to you, it possesses a method to get your attention when there’s a furnace error.

Its motherboard has twin LED lights that can display a fault code. Subject to the fault, your heater may display continuous or flashing lights.

Though there are certain elementary HVAC repairs you can complete yourself, most fixes are best taken care of by experts. When your heating system will not start or give warmth, call Lycoming Heating Company at 570-244-2510 for expert furnace repair in Williamsport.

Our experts will quickly spot and repair the issue, even if you don’t own a Lennox furnace. We can fix any types or configuration—and get the heat restored to your house without delay.


What Does the Flashing Light on My Heater Mean?

Your furnace depends on lights to flash code when it isn’t working right. It also works this setup to relay it’s running properly.

Normal heating consists of:

  • Simultaneous slow flash—heater working like it should.
  • Both lights flash fast—furnace is initiating the call for heat.

If you notice one light going on and off slowly and the other flashing fast, your heater may be experiencing a low flame signal. This can take place even when your furnace is working properly. It means the flame sensing rod may be dirty or in the bad spot on the burner. Reach out to us at 570-244-2510 for support.

Here are several other of the most routine faults for Lennox heating systems.

Heating System Will Not Kick On

Here are some of the light sequences you could notice when your heat won’t turn on or keep heating. The bulk of these issues must be taken care of by a professional, like one from Lycoming Heating Company.

  1. The duo of LED lights are off. This signifies your HVAC system might not have power. Check the breaker box to make sure the heater fuse isn’t triggered. Try resetting the fuse if it has moved into the “off” position. If it rapidly trips after a subsequent reset, don’t try to reset it again and get in touch with us us at 570-244-2510.
  2. An individual light is stable and the other is blinking slowly. This shows the flame rollout switch is may be not working right. The switch is an essential safety device that assists in preventing fires and carbon monoxide. You shouldn’t try to take care of this problem without professional help.
  3. A single light is flickering rapidly and the other is blinking slowly. This likely indicates power polarity has been reversed. Your furnace could have a wiring issue that requires professional assistance from Lycoming Heating Company.
  4. Both lights are flickering slowly. This signifies your furnace’s blower motor probably isn’t operating. This piece distributes heated air from the furnace into your rooms. We can aid in determining what’s causing an issue with this part.
  5. One light is flashing slowly and the other is flashing rapidly. This signifies your heater may have not enough voltage or a short circuit. Reach out to our technicians at 570-244-2510 for assistance.
  6. One light is flickering on, on and off while the other flashes on, off, on. This means there may be an issue with your HVAC system’s motherboard or wiring. Lycoming Heating Company can determine the problem and handle it.
  7. The pair of lights are using alternating slow flashes. This means your HVAC equipment possibly has a flame failure. There may be an issue with its gas supply, gas valve or ignitor control. Reach out to us at 570-244-2510 for assistance.
  8. One light blinks slowly while the other remains steady. This usually means your HVAC equipment’s limit switch is experiencing an error. The switch keeps your heating system from becoming too warm. Reach out to the professionals at Lycoming Heating Company for help.

Furnace Blower Runs But No Warm Air

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

  • The duo of lights display alternating fast blinks. This indicates your furnace ignitor could not be in working order. This component lights gas in your furnace to create warmth and should be serviced by a specialist from Lycoming Heating Company.

Trust Us for Professional Furnace Repair

When you need to have your heating system repaired fast, turn to the experts at Lycoming Heating Company. Our technicians will fix the problem right away and have your space feeling cozy again in no time. Contact us at 570-244-2510 or contact us online to schedule an appointment today.

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