Furnace troubleshooting

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

While your Lennox® furnace can’t chat with you, it has a process to communicate a furnace error.

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

While there are some basic HVAC fixes you can complete on your own, many tasks are best handled by experts. When your furnace won’t turn on or put out warm air, contact Carefree Heating and Cooling, LLC at 513-268-5164 for expert furnace repair in Hamilton.

Our experts will quickly determine and fix the malfunction, even if you don’t use a Lennox heater. We can repair all kinds or makes—and get the warmth returned to your house quickly.


What Does the Blinking Light on My Heating System Mean?

Your heating system uses lights to flash code when it isn’t working right. It also works this system to let you know it’s heating like it should.

Regular heating consists of:

  • Concurrent slow flash—heater operating like it should.
  • Simultaneous fast flash—furnace is beginning to call for heat.

If you notice a solitary light going on and off slowly and the other going on and off rapidly, your furnace might be having a low flame signal. This can occur even when your heating system is running correctly. It signifies the flame sensing rod may have build-up or in the wrong area on the burner. Call us at 513-268-5164 for help.

Here are several other of the most common faults for Lennox furnaces.

Furnace Refuses to Kick On

Here are many of the light sequences you might notice when your heating system will not or stay on. Most of these issues need to be repaired by a specialist, like one from Carefree Heating and Cooling, LLC.

  1. All LED lights aren’t lit. This signifies your heater might not have power. Find the breaker box to confirm the furnace fuse has not flipped. Attempt to reset the fuse if it has moved into the “off” position. If it promptly flips after a subsequent reset, leave the breaker alone and call us at 513-268-5164.
  2. One light is unchanging and the other is flashing slowly. This shows the flame rollout switch is likely malfunctioning. The part is an important safety guard that assists in avoiding fires and carbon monoxide. You shouldn’t try to handle this fault on your own.
  3. One light is blinking rapidly and the other is flashing slowly. This usually indicates power polarity has been transposed. Your heating system could have a wiring problem that requires specialized support from Carefree Heating and Cooling, LLC.
  4. The duo of lights are flickering slowly. This signifies your heating system’s blower motor probably isn’t working. This piece distributes hot air from the furnace into your residence. We can assist in pinpointing what’s causing a problem with this component.
  5. A single light is flickering slowly and the other is blinking fast. This signifies your heater could have not enough voltage or a short circuit. Contact our technicians at 513-268-5164 for support.
  6. One light is flickering on, on and off while the other blinks on, off, on. This means there may be an issue with your HVAC system’s motherboard or wiring. Carefree Heating and Cooling, LLC can determine the issue and fix it.
  7. Both lights display alternate slow blinks. This signifies your HVAC system may have a flame problem. There could be an issue with its gas supply, gas valve or ignitor control. Get in touch with us at 513-268-5164 for help.
  8. A single light blinks slowly while the other stays continuous. This typically indicates your HVAC equipment’s limit switch is experiencing an error. The switch prevents your heater from overheating. Get in touch with the pros at Carefree Heating and Cooling, LLC for assistance.

Furnace Blower Operates But No Warmth

Here’s what may be at fault when you observe your heating system’s blower fan working, but you aren’t getting any warm air.

  • The duo of lights display alternate fast flashes. This indicates your furnace ignitor could be broken. This component lights energy in your HVAC equipment to produce heat and should be repaired by a technician from Carefree Heating and Cooling, LLC.

Depend on Us for Expert Furnace Repair

When you have to get your furnace in working order without delay, depend on the specialists at Carefree Heating and Cooling, LLC. Our technicians will fix the problem promptly and have your house feeling relaxing again in no time. Contact us at 513-268-5164 or contact us online to request an appointment today.

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