Furnace troubleshooting

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

While your Lennox® furnace cannot chat with you, it has a procedure to tell you about a furnace error.

Its control board has double LED lights that can share a fault code. Subject to the fault, your heater might show steady or flashing lights.

Although there are certain elementary furnace adjustments you can finish yourself, many repairs are best handled by 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 spot and repair the fault, even if you don’t own a Lennox furnace. We can fix whichever brands or models—and get the comfort returned to your residence without delay.


What Does the Flickering Light on My Furnace Mean?

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

Regular function consists of:

  • Concurrent slow flash—heater heating like it should.
  • Concurrent fast flash—furnace is initiating the call for heat.

If you realize that one light flashing slowly and the other blinking fast, your heater might have a low flame signal. This can take place even when your heating system is running correctly. It signifies the flame sensing rod might have build-up or in the bad spot on the burner. Contact us at 803-220-0761 for support.

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

Furnace Will Not Start

Here are many of the light patterns you could notice when your heating system will not or keep running. Most of these issues have to be handled by a specialist, for instance from US Air Heating and Cooling.

  1. The pair of LED lights are off. This signifies your furnace might not have electricity. Check the breaker box to make sure the heating system fuse is not triggered. You should reset the fuse if it has moved into the “off” area. If it immediately trips after you reset it, don’t touch the breaker and contact us at 803-220-0761.
  2. A single light is stable and the other is blinking slowly. This signifies the flame rollout switch is likely open. The part is an essential safety tool that aids in stopping fires and carbon monoxide. You shouldn’t try to handle this issue on your own.
  3. A single light is flickering rapidly and the other is flickering slowly. This typically signifies power polarity has been transposed. Your furnace may have a wiring fault that needs expert assistance from US Air Heating and Cooling.
  4. The pair of lights are flickering slowly. This means your furnace’s blower motor possibly isn’t running. This piece circulates hot air from the furnace into your residence. We can help in figuring out what’s wrong with this piece.
  5. A single light is flickering slowly and the other is blinking fast. This means your HVAC system might 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 take care of it.
  7. The duo of lights display alternating slow blinks. This signifies your heating system may have a flame issue. There could be a problem with its gas supply, gas valve or ignitor control. Contact us at 803-220-0761 for assistance.
  8. A single light flickers slowly while the other is steady. This often means your HVAC equipment’s limit switch is malfunctioning. The switch keeps your furnace from becoming too warm. Call the experts at US Air Heating and Cooling for help.

Heating System Blower Works But No Warm Air

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

  • The pair of lights display alternate rapid flashes. This signifies your furnace ignitor may not be in working order. This component ignites gas in your HVAC equipment to create warmth and should be repaired by a technician from US Air Heating and Cooling.

Turn to Us for Skilled Furnace Repair

When you have to have your furnace in working order without delay, trust the professionals at US Air Heating and Cooling. Our techs will fix the fault promptly and have your house feeling relaxing again soon. Contact us at 803-220-0761 or contact us online to request an appointment right away.

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