Furnace troubleshooting

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

While your Lennox® HVAC equipment isn’t able to chat with you, it possesses a way to communicate a furnace error.

Its control board has two LED lights that can show a fault code. Based on the fault, your furnace might show continuous or flashing lights.

While there are a few elementary heating repairs you can do without an expert, most fixes are best taken care of by experts. When your heater will not turn on or put out heat, contact Strine's Heating & Air Conditioning at 717-383-4479 for skilled furnace repair in York.

Our technicians will swiftly pinpoint and handle the failure, even if you don’t own a Lennox furnace. We can repair any brands or makes—and get the warmth returned to your residence quickly.


What Does the Flickering Light on My Heater Mean?

Your furnace uses lights to flash code when it is malfunctioning. It also works these lights to let you know it’s operating properly.

Correct function consists of:

  • Both lights flash slowly—heating system working correctly.
  • Simultaneous fast flash—heating system is starting to call for heat.

If you realize that a lone light flashing slowly and the other flashing rapidly, your heating system may have a low flame signal. This can occur even when your heater is running properly. It means the flame sensing rod might need to be cleaned or in the incorrect location on the burner. Contact us at 717-383-4479 for assistance.

Here are several other of the most common errors for Lennox heating systems.

Heating System Refuses to Start

Here are some of the light patterns you could notice when your heat will not or keep heating. Most of these problems need to be repaired by a professional, such as one from Strine's Heating & Air Conditioning.

  1. Both LED lights are extinguished. This signifies your furnace might not have electricity. Go to the breaker box to ensure the heater fuse has not triggered. You should reset the fuse if it’s in the “off” area. If it rapidly turns off after a subsequent reset, don’t touch the breaker and contact us at 717-383-4479.
  2. An individual light is stable and the other is blinking slowly. This shows the flame rollout switch is possibly not working right. The switch is an important safety device that helps in avoiding fires and carbon monoxide. You shouldn’t attempt to handle this malfunction without professional help.
  3. One light is blinking rapidly and the other is blinking slowly. This often signifies power polarity has been inverted. Your furnace could have a wiring problem that needs expert assistance from Strine's Heating & Air Conditioning.
  4. The pair of lights are flickering slowly. This signifies your heater’s blower motor probably isn’t operating. This component circulates hot air from the HVAC system into your residence. We can aid in figuring out what’s causing a problem with this piece.
  5. One light is flickering slowly and the other is flickering quickly. This indicates your heating system could have insufficient voltage or a short circuit. Reach out to our experts at 717-383-4479 for assistance.
  6. One light is flashing on, on and off while the other flashes on, off, on. This signifies there may be an error with your heating system’s motherboard or wiring. Strine's Heating & Air Conditioning can locate the issue and handle it.
  7. Both lights show every other slow blinks. This indicates your furnace possibly has a flame issue. There could be an issue with its gas supply, gas valve or ignitor control. Reach out to us at 717-383-4479 for assistance.
  8. A single light blinks slowly while the other remains steady. This typically indicates your HVAC system’s limit switch is open. The switch prevents your heating system from overheating. Call the pros at Strine's Heating & Air Conditioning for assistance.

Heating System Blower Operates But No Warm Air

Here’s what could be broken when you hear your heating equipment’s blower fan working, but you aren’t getting any warmth.

  • Both lights are giving alternate rapid blinks. This means your furnace ignitor could not be working. This part lights fuel in your heater to make warm air and should be repaired by a technician from Strine's Heating & Air Conditioning.

Turn to Us for Expert Furnace Repair

When you need to have your heating system in working order fast, depend on the professionals at Strine's Heating & Air Conditioning. Our technicians will take care of the problem right away and have your residence feeling relaxing again in no time. Call us at 717-383-4479 or contact us online to request an appointment now.

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