Furnace troubleshooting

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

While your Lennox® furnace can’t speak to you, it possesses a process to communicate a furnace error.

Its control board has a set of LED lights that can share a fault code. Depending on the malfunction, your furnace might 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 specialists will quickly spot and fix the malfunction, even if you don’t use a Lennox heating system. We can service all types or models—and get the warmth returned to your residence without delay.


What Does the Blinking Light on My Heater 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:

  • Simultaneous slow flash—heater operating properly.
  • Both lights flash fast—heating system is starting to call for heat.

If you notice a solitary light blinking slowly and the other blinking rapidly, your furnace could be having a low flame signal. This can take place even when your heating system is running correctly. It signifies the flame sensing rod could need to be cleaned or in the wrong area on the burner. Call us at 513-268-5164 for assistance.

Here are some of the most common issues for Lennox furnaces.

Furnace Will Not Start

Here are a few of the light patterns you might observe when your heating system refuses to or stay on. Most of these problems must 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 immediately flips following a 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 probably not working right. The part is an important safety guard that aids in avoiding fires and carbon monoxide. You shouldn’t try to handle this fault without professional help.
  3. One light is blinking fast and the other is flashing slowly. This typically indicates power polarity has been transposed. Your heater might have a wiring problem that requires expert support from Carefree Heating and Cooling, LLC.
  4. The duo of lights are blinking slowly. This indicates your heater’s blower motor probably isn’t working. This component distributes heated air from the furnace into your residence. We can aid in pinpointing what’s causing an issue with this component.
  5. An individual light is flickering slowly and the other is flickering rapidly. This signifies your furnace 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 flickers on, off, on. This means there may be an issue with your HVAC system’s control panel or wiring. Carefree Heating and Cooling, LLC can determine the issue and fix it.
  7. Both lights are using alternate slow blinks. This indicates 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. An individual light blinks slowly while the other remains continuous. This typically indicates your HVAC equipment’s limit switch is experiencing an error. The switch prevents your heating system from overheating. Get in touch with the pros at Carefree Heating and Cooling, LLC for assistance.

Furnace Blower Works But No Warmth

Here’s what may be at fault when you observe your furnace’s blower fan on, but you aren’t getting any heat.

  • The pair of lights display every other fast flashes. This signifies your furnace ignitor might be broken. This component lights energy in your HVAC equipment to produce heat and should be fixed by a technician from Carefree Heating and Cooling, LLC.

Turn to Us for Expert Furnace Repair

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

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