Furnace troubleshooting

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

While your Lennox® furnace isn’t able to chat with you, it possesses a process to tell you about a furnace error.

Its control board has twin LED lights that can show a fault code. Based on the fault, your heater might show steady or flashing lights.

Although there are certain elementary furnace adjustments you can do yourself, many repairs are best left to HVAC technicians. When your heater refuses to start or provide warm air, get in touch with US Air Heating and Cooling at 803-220-0761 for expert furnace repair in Rock Hill.

Our technicians will swiftly determine and take care of the fault, even if you don’t use a Lennox furnace. We can fix whichever brands or makes—and get the comfort reintroduced to your house without delay.


What Does the Flashing Light on My Furnace Mean?

Your heater uses lights to flash code when it isn’t working right. It also engages these lights to tell you it’s working correctly.

Regular function consists of:

  • Concurrent slow flash—furnace heating properly.
  • Concurrent fast flash—heating system is initiating the call for heat.

If you realize that a solitary light flashing slowly and the other going on and off fast, your heating system could be experiencing a low flame signal. This can occur even when your heating system is running correctly. It signifies the flame sensing rod might need to be cleaned or in the bad spot on the burner. Contact us at 803-220-0761 for support.

Here are several other of the most routine faults for Lennox furnaces.

Furnace Will Not Start

Here are a few of the light patterns you could observe when your heating system refuses to or keep running. Most of these problems have to be fixed by a specialist, for instance from US Air Heating and Cooling.

  1. The pair of LED lights are off. This means your heating system might not be receiving power. Find the breaker box to make sure the heating system fuse is not flipped. You should reset the fuse if it has moved into the “off” area. If it immediately trips after you reset it, don’t try to reset it again and contact us at 803-220-0761.
  2. A single light is stable and the other is flickering slowly. This signifies the flame rollout switch is probably open. The part is a critical safety tool that aids in stopping fires and carbon monoxide. You shouldn’t try to handle this issue on your own.
  3. An individual light is blinking rapidly and the other is flickering slowly. This usually indicates power polarity has been inverted. Your furnace may have a wiring fault that calls for expert assistance from US Air Heating and Cooling.
  4. Both lights are blinking slowly. This means your furnace’s blower motor possibly isn’t operating. This piece circulates heated air from the heater into your residence. We can help in pinpointing what’s wrong with this piece.
  5. An individual light is blinking slowly and the other is blinking fast. This means your HVAC system could have not enough voltage or a short circuit. Get in touch with our specialists at 803-220-0761 for assistance.
  6. One light is flickering on, on and off while the other flickers on, off, on. This means there may be trouble with your furnace’s control board or wiring. US Air Heating and Cooling can find the problem and repair it.
  7. The duo of lights are using alternating slow flickers. This signifies your heating system may have a flame failure. There could be a problem with its gas supply, gas valve or ignitor control. Contact us at 803-220-0761 for assistance.
  8. An individual light blinks slowly while the other is steady. This typically means your HVAC equipment’s limit switch is malfunctioning. The switch keeps your HVAC system from becoming too warm. Call the professionals at US Air Heating and Cooling for help.

Heater Blower Operates But No Warmth

Here’s what might be wrong when you notice your furnace’s blower fan working, but you aren’t gaining any warm air.

  • The duo of lights display every other rapid flashes. This indicates your furnace ignitor may not be in working order. This component ignites gas in your HVAC equipment to create warm air and should be fixed by a technician from US Air Heating and Cooling.

Depend on Us for Skilled Furnace Repair

When you have to have your heating system repaired without delay, trust the specialists at US Air Heating and Cooling. Our techs will fix the fault promptly and have your house feeling relaxing again in a short time. Contact us at 803-220-0761 or contact us online to request an appointment now.

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