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

December 06, 2019

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

Its control panel has a set of LED lights that can display a fault code. Depending on the problem, your furnace might show continuous or flashing lights.

While there are a few elementary HVAC adjustments you can take care of without an expert, many services are best taken care of by the professionals. When your furnace will not kick on or provide warm air, call Phelps Heating & Cooling at 270-358-3167 for professional furnace repair in Hodgenville.

Our specialists will quickly diagnose and repair the malfunction, even if you don’t own a Lennox furnace. We can fix whichever brands or models—and get the comfort returned to your house quickly.


What Does the Flickering Light on My Heating System Mean?

Your furnace relies on lights to flash code when it requires repairs. It also engages these lights to relay it’s working 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 one light flashing slowly and the other blinking rapidly, your heating system might be having a low flame signal. This can take place even when your heater is running correctly. It signifies the flame sensing rod could have build-up or in the bad location on the burner. Call us at 270-358-3167 for support.

Here are a few other of the most typical errors for Lennox heaters.

Heating System Refuses to Start

Here are many of the light sequences you might notice when your furnace will not or stay on. The majority of these issues need to be handled by a professional, like one from Phelps Heating & Cooling.

  1. All LED lights are extinguished. This indicates your furnace might not have power. Check the breaker box to make sure the furnace fuse has not tripped. Attempt to reset the fuse if it has moved into the “off” position. If it immediately turns off after you reset it, don’t touch the breaker and get in touch with us us at 270-358-3167.
  2. One light is solid and the other is flashing slowly. This implies the flame rollout switch is may be open. The switch is an essential safety guard that aids in stopping fires and carbon monoxide. You shouldn’t attempt to handle this problem without professional help.
  3. One light is blinking quickly and the other is flickering slowly. This typically means power polarity has been reversed. Your heater may have a wiring error that requires specialized assistance from Phelps Heating & Cooling.
  4. The pair of lights are flickering slowly. This indicates your heater’s blower motor possibly isn’t working. This component sends hot air from the heater into your residence. We can help in determining what’s causing an issue with this piece.
  5. A single light is flashing slowly and the other is flickering quickly. This means your HVAC system could have not enough voltage or a short circuit. Call our technicians at 270-358-3167 for support.
  6. One light is flashing on, on and off while the other flashes on, off, on. This indicates there might be a problem with your HVAC system’s control board or wiring. Phelps Heating & Cooling can determine the fault and take care of it.
  7. The duo of lights display alternate slow flashes. This means your furnace likely has a flame error. There may be a problem with its gas supply, gas valve or ignitor control. Get in touch with us at 270-358-3167 for help.
  8. One light flickers slowly while the other stays continuous. This usually signifies your HVAC equipment’s limit switch is open. The switch keeps your heating system from becoming too warm. Contact the specialists at Phelps Heating & Cooling for help.

Furnace Blower Operates But No Warm Air

Here’s what could be wrong when you observe your heater’s blower fan running, but you aren’t getting any warmth.

  • Both lights are showing every other rapid flickers. This indicates your furnace ignitor may be broken. This component lights energy in your furnace to produce warmth and should be repaired by a professional from Phelps Heating & Cooling.

Turn to Us for Professional Furnace Repair

When you need to get your HVAC equipment in working order fast, depend on the specialists at Phelps Heating & Cooling. Our pros will fix the error promptly and have your residence feeling cozy again soon. Get in touch with us at 270-358-3167 or contact us online to get an appointment today.