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

December 06, 2019

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

Its motherboard has twin LED lights that can share a fault code. Depending on the issue, your furnace might use continuous or flashing lights.

Although there are a few simple furnace fixes you can take care of on your own, many services are best left to the professionals. When your heating system refuses to start or give heat, reach out to Pliescott HVAC Services LLC at 410-228-4822 for experienced furnace repair in Cambridge.

Our technicians will speedily discover and handle the failure, even if you don’t use a Lennox furnace. We can service any brands or makes—and get the warmth restored to your house without delay.


What Does the Flickering Light on My Heating System Mean?

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

Normal heating includes:

  • Concurrent slow flash—heating system working correctly.
  • Simultaneous fast flash—heating system is initiating the call for heat.

If you notice a lone light going on and off slowly and the other blinking fast, your furnace could be having a low flame signal. This can happen even when your heater is heating like it should. It signifies the flame sensing rod might have build-up or in the wrong spot on the burner. Contact us at 410-228-4822 for help.

Here are a few other of the most routine issues for Lennox furnaces.

Heater Won’t Turn On

Here are a few of the light patterns you could observe when your heating system refuses to or keep running. The bulk of these issues need to be repaired by an expert, for instance from Pliescott HVAC Services LLC .

  1. All LED lights are extinguished. This signifies your furnace might not have power. Examine the breaker box to make sure the heater fuse is not triggered. Try resetting the fuse if it is in the “off” position. If it promptly turns off after you reset it, don’t touch the breaker and contact us at 410-228-4822.
  2. An individual light is stable and the other is flashing slowly. This signifies the flame rollout switch is may be not working right. The component is a critical safety device that assists in avoiding fires and carbon monoxide. You shouldn’t attempt to repair this fault on your own.
  3. A single light is blinking rapidly and the other is blinking slowly. This likely means power polarity has been inverted. Your furnace might have a wiring error that requires professional support from Pliescott HVAC Services LLC .
  4. The duo of lights are flashing slowly. This signifies your furnace’s blower motor possibly isn’t running. This component distributes hot air from the heater into your house. We can assist in determining what’s causing an issue with this component.
  5. One light is flickering slowly and the other is blinking quickly. This signifies your heating system might have low voltage or a short circuit. Get in touch with our professionals at 410-228-4822 for help.
  6. One light is flickering on, on and off while the other flashes on, off, on. This signifies there might be a fault with your heater’s control board or wiring. Pliescott HVAC Services LLC can determine the issue and fix it.
  7. The pair of lights are using every other slow flashes. This indicates your heater possibly has a flame error. There could be an issue with its gas supply, gas valve or ignitor control. Contact us at 410-228-4822 for help.
  8. A single light flashes slowly while the other is solid. This typically indicates your heating system’s limit switch is open. The switch prevents your heating system from becoming too warm. Call the specialists at Pliescott HVAC Services LLC for support.

Heater Blower Operates But No Warm Air

Here’s what may be wrong when you hear your heating system’s blower fan on, but you aren’t getting any heat.

  • Both lights are showing alternating rapid flickers. This signifies your furnace ignitor could be broken. This part lights fuel in your furnace to create heat and should be repaired by a technician from Pliescott HVAC Services LLC .

Trust Us for Skilled Furnace Repair

When you have to have your heater fixed without delay, depend on the experts at Pliescott HVAC Services LLC . Our technicians will repair the fault right away and have your house feeling comfortable again in a short time. Contact us at 410-228-4822 or contact us online to request an appointment now.