Furnace troubleshooting

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

While your Lennox® heating system isn’t able to talk to you, it has a procedure to get your attention when there’s a furnace error.

Its motherboard has two LED lights that can display a fault code. Depending on the problem, your heating system could use solid or flashing lights.

While there are some basic HVAC fixes you can finish yourself, the majority of repairs are best left to HVAC technicians. When your heater won’t start or deliver heat, reach out to McCune Heating & Cooling at 316-469-7994 for expert furnace repair in Augusta.

Our technicians will rapidly diagnose and fix the fault, even if you don’t use a Lennox furnace. We can service all brands or makes—and get the heat reintroduced to your house fast.


What Does the Blinking Light on My Heater Mean?

Your heating system relies on lights to flash code when it needs to be repaired. It also uses these lights to tell you it’s heating like it should.

Regular heating consists of:

  • Both lights flash slowly—heater heating like it should.
  • Concurrent fast flash—furnace is starting to call for heat.

If you see a lone light flashing slowly and the other blinking quickly, your furnace might be having a low flame signal. This can happen even when your furnace is working properly. It signifies the flame sensing rod may need to be cleaned or in the bad spot on the burner. Contact us at 316-469-7994 for help.

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

Heater Won’t Kick On

Here are some of the light patterns you might observe when your furnace won’t turn on or stay on. Most of these problems must be handled by an expert, like one from McCune Heating & Cooling.

  1. The pair of LED lights are off. This means your furnace might not have power. Go to the breaker box to confirm the heater fuse hasn’t flipped. You should reset the fuse if it’s in the “off” spot. If it promptly turns off after a subsequent reset, don’t touch the breaker and contact us at 316-469-7994.
  2. An individual light is stable and the other is flickering slowly. This implies the flame rollout switch is probably not working right. The part is a critical safety tool that helps in stopping fires and carbon monoxide. You shouldn’t seek to handle this issue yourself.
  3. A single light is flashing rapidly and the other is flickering slowly. This usually signifies power polarity has been reversed. Your heating system could have a wiring problem that needs professional support from McCune Heating & Cooling.
  4. Both lights are blinking slowly. This means your furnace’s blower motor possibly isn’t running. This piece moves hot air from the heater into your house. We can aid in determining what’s causing a problem with this piece.
  5. An individual light is blinking slowly and the other is flickering rapidly. This indicates your heating system might have low voltage or a short circuit. Contact our technicians at 316-469-7994 for help.
  6. One light is flashing on, on and off while the other flashes on, off, on. This indicates there might be a malfunction with your heater’s control board or wiring. McCune Heating & Cooling can pinpoint the problem and fix it.
  7. The pair of lights are using alternating slow flickers. This indicates your heating system possibly has a flame issue. There may be an issue with its gas supply, gas valve or ignitor control. Call us at 316-469-7994 for support.
  8. A single light flashes slowly while the other is solid. This often signifies your furnace’s limit switch is malfunctioning. The switch stops your HVAC system from becoming too warm. Contact the pros at McCune Heating & Cooling for support.

Heating System Blower Operates But No Heat

Here’s what might be wrong when you hear your heater’s blower fan on, but you aren’t gaining any heat.

  • The pair of lights are giving alternate rapid flashes. This signifies your furnace ignitor may not be in working order. This part lights gas in your HVAC equipment to make warmth and should be repaired by a technician from McCune Heating & Cooling.

Turn to Us for Skilled Furnace Repair

When you need to get your heater repaired fast, trust the technicians at McCune Heating & Cooling. Our pros will take care of the issue without delay and have your residence feeling cozy again in a short time. Contact us at 316-469-7994 or contact us online to schedule an appointment today.

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