Furnace troubleshooting

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

While your Lennox® furnace cannot speak to you, it possesses a method to tell you about a furnace error.

Its control board has double LED lights that can show a fault code. Based on the malfunction, your heating system may use continuous or flashing lights.

Although there are certain basic HVAC fixes you can finish on your own, many tasks are best handled by experts. When your furnace refuses to kick on or deliver warm air, contact PWA Heating & Cooling Inc at 815-410-1231 for professional furnace repair in Plainfield.

Our specialists will quickly detect and handle the problem, even if you don’t own a Lennox furnace. We can fix whichever types or configuration—and get the heat restored to your home quickly.


What Does the Blinking Light on My Furnace Mean?

Your heating system depends on lights to flash code when it requires repairs. It also works this setup to relay it’s heating correctly.

Regular operation includes:

  • Simultaneous slow flash—heater running correctly.
  • Simultaneous fast flash—heater is beginning to call for heat.

If you realize that a solitary light flashing slowly and the other flashing rapidly, your furnace might have a low flame signal. This can take place even when your heating system is running correctly. It means the flame sensing rod might have build-up or in the incorrect area on the burner. Contact us at 815-410-1231 for support.

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

Furnace Refuses to Turn On

Here are many of the light sequences you may see when your heat refuses to or keep operating. The majority of these issues must be taken care of by a professional, like one from PWA Heating & Cooling Inc.

  1. The duo of LED lights aren’t lit. This means your HVAC system might not have electricity. Examine the breaker box to ensure the heater fuse isn’t triggered. Try resetting the fuse if it’s in the “off” position. If it instantly trips after you reset it, don’t touch the breaker and contact us at 815-410-1231.
  2. An individual light is solid and the other is flickering slowly. This means the flame rollout switch is likely malfunctioning. The part is an essential safety mechanism that aids in stopping fires and carbon monoxide. You shouldn’t attempt to fix this problem yourself.
  3. An individual light is flashing rapidly and the other is flickering slowly. This likely means power polarity has been reversed. Your heater may have a wiring problem that needs professional assistance from PWA Heating & Cooling Inc.
  4. Both lights are flashing slowly. This indicates your furnace’s blower motor possibly isn’t working. This piece sends hot air from the heating system into your residence. We can help in determining what’s causing an issue with this component.
  5. An individual light is blinking slowly and the other is flickering quickly. This means your heating system may have low voltage or a short circuit. Reach out to our technicians at 815-410-1231 for support.
  6. One light is flashing on, on and off while the other flashes on, off, on. This means there may be an error with your heater’s control panel or wiring. PWA Heating & Cooling Inc can determine the problem and handle it.
  7. The pair of lights display alternating slow flickers. This means your HVAC equipment likely has a flame problem. There could be an issue with its gas supply, gas valve or ignitor control. Reach out to us at 815-410-1231 for support.
  8. A single light flashes slowly while the other is continuous. This often means your heating system’s limit switch is open. The switch stops your HVAC equipment from becoming too warm. Get in touch with the experts at PWA Heating & Cooling Inc for help.

Furnace Blower Operates But No Warm Air

Here’s what might be wrong when you notice your heater’s blower fan working, but you aren’t gaining any warm air.

  • The pair of lights are giving alternating quick flickers. This indicates your furnace ignitor may not be working. This piece kindles energy in your heater to create heat and should be serviced by an expert from PWA Heating & Cooling Inc.

Turn to Us for Skilled Furnace Repair

When you have to get your furnace fixed quickly, depend on the technicians at PWA Heating & Cooling Inc. Our techs will repair the issue without delay and have your space feeling relaxing again soon. Contact us at 815-410-1231 or contact us online to schedule an appointment today.

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