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

December 06, 2019

While your Lennox® heating system can’t speak to you, it does have a method to get your attention when there’s a furnace error.

Its motherboard has a set of LED lights that can show a fault code. Depending on the failure, your heating system might use continuous or flashing lights.

While there are certain simple furnace repairs you can do on your own, many fixes are best handled by HVAC technicians. When your heating system won’t kick on or deliver warm air, contact Tri County Climate Control LLC at 541-238-2797 for skilled furnace repair in Bend.

Our experts will swiftly detect and fix the problem, even if you don’t use a Lennox heating system. We can service any kinds or models—and get the warmth restored to your residence quickly.


What Does the Blinking Light on My Heater Mean?

Your heating system relies on lights to flash code when it is malfunctioning. It also engages this setup to relay it’s working correctly.

Correct function includes:

  • Concurrent slow flash—furnace working correctly.
  • Simultaneous fast flash—heater is beginning to call for heat.

If you notice a solitary light blinking slowly and the other blinking rapidly, your heating system may be experiencing a low flame signal. This can happen even when your heating system is operating properly. It indicates the flame sensing rod may need to be cleaned or in the bad location on the burner. Reach out to us at 541-238-2797 for help.

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

Heating System Refuses to Start

Here are some of the light patterns you might observe when your furnace will not or keep running. The majority of these errors have to be repaired by a technician, like one from Tri County Climate Control LLC.

  1. Both LED lights aren’t lit. This signifies your HVAC system might not have electricity. Go to the breaker box to confirm the furnace fuse has not tripped. Try resetting the fuse if it is in the “off” spot. If it instantly flips following a reset, don’t touch the breaker and contact us at 541-238-2797.
  2. An individual light is stable and the other is blinking slowly. This means the flame rollout switch is probably open. The switch is a critical safety device that helps in preventing fires and carbon monoxide. You shouldn’t try to fix this issue yourself.
  3. An individual light is blinking rapidly and the other is flashing slowly. This usually signifies power polarity has been inverted. Your heating system may have a wiring error that calls for professional assistance from Tri County Climate Control LLC.
  4. The pair of lights are blinking slowly. This means your heater’s blower motor likely isn’t operating. This component circulates warm air from the furnace into your home. We can assist in pinpointing what’s causing a problem with this part.
  5. One light is blinking slowly and the other is flashing quickly. This signifies your heater might have not enough voltage or a short circuit. Call our technicians at 541-238-2797 for help.
  6. One light is blinking on, on and off while the other blinks on, off, on. This signifies there may be an error with your furnace’s motherboard or wiring. Tri County Climate Control LLC can determine the problem and fix it.
  7. The duo of lights are using alternate slow blinks. This signifies your HVAC system may have a flame problem. There may be an issue with its gas supply, gas valve or ignitor control. Get in touch with us at 541-238-2797 for support.
  8. A single light flickers slowly while the other remains continuous. This typically indicates your HVAC equipment’s limit switch is malfunctioning. The switch prevents your HVAC equipment from becoming too warm. Contact the professionals at Tri County Climate Control LLC for assistance.

Furnace Blower Works But No Warm Air

Here’s what may be at fault when you observe your heater’s blower fan running, but you aren’t receiving any heated air.

  • Both lights are giving alternate quick flickers. This signifies your furnace ignitor could not be working. This part kindles energy in your HVAC equipment to make warmth and should be repaired by a technician from Tri County Climate Control LLC.

Depend on Us for Skilled Furnace Repair

When you have to have your furnace fixed quickly, trust the professionals at Tri County Climate Control LLC. Our technicians will fix the issue quickly and have your house feeling comfortable again in no time. Reach out to us at 541-238-2797 or contact us online to schedule an appointment right away.