Furnace troubleshooting

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

While your Lennox® HVAC equipment isn’t able to speak to you, it does have a process to communicate a furnace error.

Its control panel has twin LED lights that can show a fault code. Subject to the fault, your heating system might show steady or flashing lights.

Although there are certain elementary furnace repairs you can finish without an expert, most tasks are best left to HVAC technicians. When your heater won’t kick on or put out warmth, get in touch with Street Heating and Cooling at 605-206-3915 for expert furnace repair in Rapid City.

Our technicians will rapidly diagnose and handle the problem, even if you don’t have a Lennox heater. We can service any types or models—and get the heat returned to your residence fast.


What Does the Blinking Light on My Furnace Mean?

Your furnace depends on lights to flash code when it needs to be repaired. It also works these lights to tell you it’s operating correctly.

Normal heating consists of:

  • Concurrent slow flash—furnace running correctly.
  • Simultaneous fast flash—heater is initiating the call for heat.

If you realize that one light blinking slowly and the other flashing quickly, your heating system may have a low flame signal. This can occur even when your heating system is heating correctly. It means the flame sensing rod might have build-up or in the wrong spot on the burner. Call us at 605-206-3915 for help.

Here are some of the most routine problems for Lennox heating systems.

Furnace Will Not Kick On

Here are many of the light patterns you might see when your heat won’t turn on or keep heating. The bulk of these issues need to be fixed by an expert, for instance from Street Heating and Cooling.

  1. All LED lights are extinguished. This indicates your furnace might not have power. Look at the breaker box to ensure the heater fuse hasn’t triggered. Try resetting the fuse if it’s in the “off” area. If it instantly trips after you reset it, leave the breaker alone and call us at 605-206-3915.
  2. One light is stable and the other is flashing slowly. This signifies the flame rollout switch is probably not working right. The part is an essential safety device that assists in avoiding fires and carbon monoxide. You shouldn’t try to fix this fault without professional help.
  3. One light is flickering fast and the other is flashing slowly. This likely signifies power polarity has been inverted. Your furnace might have a wiring problem that requires professional aid from Street Heating and Cooling.
  4. The pair of lights are flashing slowly. This means your heater’s blower motor likely isn’t operating. This piece sends warm air from the heater into your house. We can assist in determining what’s causing a problem with this part.
  5. One light is flickering slowly and the other is flashing rapidly. This means your heating system might have insufficient voltage or a short circuit. Contact our experts at 605-206-3915 for support.
  6. One light is blinking on, on and off while the other blinks on, off, on. This means there could be an issue with your heater’s control board or wiring. Street Heating and Cooling can pinpoint the error and take care of it.
  7. The duo of lights display alternate slow flashes. This indicates your heater possibly has a flame problem. There could be an issue with its gas supply, gas valve or ignitor control. Call us at 605-206-3915 for assistance.
  8. One light flickers slowly while the other stays continuous. This often signifies your furnace’s limit switch is not working. The switch keeps your HVAC system from becoming too warm. Reach out to the pros at Street Heating and Cooling for help.

Heating System Blower Works But No Warmth

Here’s what may be wrong when you notice your heating equipment’s blower fan on, but you aren’t receiving any warm air.

  • The pair of lights are giving alternate quick flickers. This signifies your furnace ignitor might not be in working order. This part kindles gas in your HVAC equipment to produce warm air and should be fixed by a specialist from Street Heating and Cooling.

Depend on Us for Professional Furnace Repair

When you have to have your heating system in working order fast, turn to the experts at Street Heating and Cooling. Our techs will fix the issue without delay and have your house feeling comfortable again in a short time. Call us at 605-206-3915 or contact us online to schedule an appointment now.

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