Furnace troubleshooting

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

While your Lennox® HVAC equipment can’t speak to you, it possesses a procedure to tell you about a furnace error.

Its motherboard has a set of LED lights that can show a fault code. Depending on the fault, your furnace could show solid or flashing lights.

Although there are various simple HVAC repairs you can finish without an expert, most fixes are best left to HVAC technicians. When your heating system will not kick on or deliver warmth, call Jent Mechanical LLC at 937-845-1111 for expert furnace repair in Dayton.

Our technicians will speedily determine and take care of the malfunction, even if you don’t use a Lennox furnace. We can service all types or models—and get the warmth returned to your residence quickly.


What Does the Flashing Light on My Heater Mean?

Your furnace relies on lights to flash code when it needs to be repaired. It also works this setup to relay it’s operating like it should.

Normal operation consists of:

  • Simultaneous slow flash—heater working like it should.
  • Concurrent fast flash—heater is starting to call for heat.

If you realize that a lone light flashing slowly and the other flashing rapidly, your furnace might be experiencing a low flame signal. This can happen even when your heater is running like it should. It indicates the flame sensing rod may be dirty or in the incorrect area on the burner. Call us at 937-845-1111 for assistance.

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

Heater Refuses to Kick On

Here are some of the light sequences you could notice when your furnace will not or keep operating. The bulk of these problems need to be taken care of by a professional, for instance from Jent Mechanical LLC.

  1. The duo of LED lights aren’t lit. This indicates your HVAC system might not have electricity. Check the breaker box to make sure the furnace fuse isn’t triggered. Try resetting the fuse if it is in the “off” area. If it immediately flips following a reset, don’t try to reset it again and call us at 937-845-1111.
  2. One light is continuous and the other is flashing slowly. This shows the flame rollout switch is probably malfunctioning. The switch is an essential safety guard that helps in preventing fires and carbon monoxide. You shouldn’t try to fix this problem on your own.
  3. One light is blinking quickly and the other is flashing slowly. This usually indicates power polarity has been transposed. Your heater could have a wiring fault that calls for expert help from Jent Mechanical LLC.
  4. The duo of lights are blinking slowly. This indicates your heater’s blower motor probably isn’t working. This part moves warm air from the HVAC system into your home. We can aid in pinpointing what’s wrong with this component.
  5. One light is blinking slowly and the other is flashing quickly. This signifies your heater could have not enough voltage or a short circuit. Reach out to our technicians at 937-845-1111 for help.
  6. One light is flickering on, on and off while the other flickers on, off, on. This means there could be a malfunction with your heating system’s motherboard or wiring. Jent Mechanical LLC can find the error and take care of it.
  7. The duo of lights are using alternate slow flashes. This means your heating system likely has a flame issue. There could be an issue with its gas supply, gas valve or ignitor control. Reach out to us at 937-845-1111 for support.
  8. A single light flashes slowly while the other remains solid. This usually signifies your heating system’s limit switch is open. The switch prevents your heating system from overheating. Reach out to the experts at Jent Mechanical LLC for help.

Heater Blower Operates But No Heat

Here’s what may be at fault when you notice your heating system’s blower fan running, but you aren’t gaining any warmth.

  • Both lights are showing every other fast blinks. This signifies your furnace ignitor might not be working. This piece kindles gas in your heating system to create warmth and should be repaired by an expert from Jent Mechanical LLC.

Turn to Us for Expert Furnace Repair

When you need to have your heater in working order quickly, turn to the specialists at Jent Mechanical LLC. Our pros will handle the fault promptly and have your space feeling relaxing again in no time. Contact us at 937-845-1111 or contact us online to schedule an appointment right away.

Back To Blog