Furnace troubleshooting

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

While your Lennox® HVAC equipment isn’t able to chat with you, it has a procedure to tell you about a furnace error.

Its control board has twin LED lights that can share a fault code. Based on the failure, your heater may show continuous or flashing lights.

While there are some elementary heating repairs you can complete on your own, many services are best left to experts. When your furnace will not start or provide warm air, call Kowalski Heating, Cooling & Plumbing at 724-370-0141 for skilled furnace repair in McMurray.

Our specialists will quickly determine and handle the issue, even if you don’t own a Lennox heater. We can repair any types or models—and get the comfort reintroduced to your home quickly.


What Does the Flashing Light on My Furnace Mean?

Your heater depends on lights to flash code when it needs to be repaired. It also uses this system to let you know it’s heating like it should.

Normal heating involves:

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

If you notice one light flashing slowly and the other blinking rapidly, your heater might have a low flame signal. This can take place even when your furnace is operating like it should. It signifies the flame sensing rod may need to be cleaned or in the incorrect location on the burner. Call us at 724-370-0141 for assistance.

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

Furnace Will Not Turn On

Here are some of the light arrangements you could observe when your furnace refuses to or keep operating. The bulk of these problems have to be repaired by a professional, such as one from Kowalski Heating, Cooling & Plumbing.

  1. All LED lights aren’t lit. This signifies your HVAC system might not be receiving power. Check the breaker box to ensure the heating system fuse hasn’t flipped. Attempt to reset the fuse if it’s in the “off” position. If it rapidly trips after a subsequent reset, don’t try to reset it again and get in touch with us us at 724-370-0141.
  2. An individual light is continuous and the other is flickering slowly. This shows the flame rollout switch is possibly not working right. The part is an essential safety mechanism that helps in stopping fires and carbon monoxide. You shouldn’t try to handle this issue yourself.
  3. One light is flashing fast and the other is flickering slowly. This often indicates power polarity has been reversed. Your heating system might have a wiring error that needs expert assistance from Kowalski Heating, Cooling & Plumbing.
  4. Both lights are flickering slowly. This means your heater’s blower motor possibly isn’t running. This component sends heated air from the heating system into your rooms. We can assist in figuring out what’s causing an issue with this piece.
  5. An individual light is blinking slowly and the other is flickering quickly. This indicates your HVAC system might have not enough voltage or a short circuit. Call our specialists at 724-370-0141 for help.
  6. One light is flickering 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. Kowalski Heating, Cooling & Plumbing can locate the issue and repair it.
  7. The pair of lights are using alternate slow flickers. This signifies your heater likely has a flame failure. There could be a problem with its gas supply, gas valve or ignitor control. Contact us at 724-370-0141 for support.
  8. One light flickers slowly while the other stays steady. This often indicates your heater’s limit switch is open. The switch stops your HVAC system from overheating. Reach out to the experts at Kowalski Heating, Cooling & Plumbing for help.

Heater Blower Runs But No Heat

Here’s what could be at fault when you notice your heating equipment’s blower fan working, but you aren’t gaining any warmth.

  • Both lights are giving alternating fast flickers. This signifies your furnace ignitor might not be in working order. This part ignites gas in your furnace to produce warmth and should be repaired by a technician from Kowalski Heating, Cooling & Plumbing.

Depend on Us for Professional Furnace Repair

When you have to get your furnace fixed without delay, trust the professionals at Kowalski Heating, Cooling & Plumbing. Our techs will fix the problem right away and have your space feeling cozy again in a short time. Get in touch with us at 724-370-0141 or contact us online to request an appointment right away.

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