Furnace troubleshooting

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

While your Lennox® furnace isn’t able to chat with you, it possesses a method to tell you about a furnace error.

Its control board has twin LED lights that can share a fault code. Subject to the problem, your heating system may use continuous or flashing lights.

Though there are certain simple heating adjustments you can do without an expert, many services are best handled by HVAC technicians. 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 speedily detect and handle the problem, even if you don’t use a Lennox furnace. We can fix whichever kinds or configuration—and get the heat restored to your home without delay.


What Does the Blinking Light on My Furnace Mean?

Your heater relies on lights to flash code when it requires repairs. It also works this system to let you know it’s heating like it should.

Regular operation includes:

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

If you notice a solitary light flashing slowly and the other flashing fast, your furnace might have a low flame signal. This can take place even when your heater is running correctly. It means the flame sensing rod might have build-up or in the wrong location on the burner. Contact us at 815-410-1231 for support.

Here are several other 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, such as one from PWA Heating & Cooling Inc.

  1. The duo of LED lights aren’t lit. This means your HVAC system might not be receiving power. Examine the breaker box to confirm the heating system 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 unchanging and the other is flickering slowly. This shows the flame rollout switch is likely malfunctioning. The part is an essential safety tool that assists in stopping fires and carbon monoxide. You shouldn’t attempt to take care of this problem yourself.
  3. An individual light is flashing fast and the other is blinking 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. The pair of lights are flashing slowly. This signifies your furnace’s blower motor likely isn’t working. This piece sends heated air from the heating system into your residence. We can help in determining what’s causing a problem with this component.
  5. A single light is blinking slowly and the other is blinking 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 are using alternating slow blinks. This means your HVAC equipment possibly 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 furnace’s limit switch is malfunctioning. The switch keeps your HVAC equipment from becoming too warm. Contact the experts at PWA Heating & Cooling Inc for help.

Furnace Blower Works But No Warm Air

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

  • The pair of lights are showing alternating quick flickers. This signifies your furnace ignitor may be broken. 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, trust the technicians at PWA Heating & Cooling Inc. Our techs will repair the issue promptly 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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