Furnace troubleshooting

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

While your Lennox® furnace cannot talk to you, it has a procedure to get your attention when there’s a furnace error.

Its control board has a set of LED lights that can display a fault code. Subject to the malfunction, your heater could show continuous or flashing lights.

Though there are some elementary HVAC fixes you can do yourself, many repairs are best left to HVAC technicians. When your furnace won’t start or deliver warm air, reach out to Central Heating & Plumbing at 724-401-1843 for expert furnace repair in New Castle.

Our specialists will swiftly pinpoint and take care of the breakdown, even if you don’t own a Lennox heater. We can fix all brands or configuration—and get the comfort restored to your home quickly.


What Does the Blinking Light on My Heating System Mean?

Your heater depends on lights to flash code when it requires repairs. It also uses this setup to let you know it’s running correctly.

Regular operation includes:

  • Concurrent slow flash—furnace running properly.
  • Both lights flash fast—heater is starting to call for heat.

If you realize that a lone light going on and off slowly and the other flashing rapidly, your furnace might have a low flame signal. This can occur even when your heating system is heating correctly. It means the flame sensing rod could be dirty or in the incorrect area on the burner. Contact us at 724-401-1843 for help.

Here are some of the most typical errors for Lennox heaters.

Furnace Won’t Kick On

Here are many of the light sequences you might notice when your heating system will not or keep heating. The bulk of these issues have to be handled by a specialist, for instance from Central Heating & Plumbing.

  1. The pair of LED lights aren’t lit. This means your HVAC system might not be receiving power. Look at the breaker box to make sure the furnace fuse hasn’t triggered. Attempt to reset the fuse if it has moved into the “off” area. If it promptly trips following a reset, don’t touch the breaker and contact us at 724-401-1843.
  2. A single light is continuous and the other is blinking slowly. This means the flame rollout switch is may be malfunctioning. The switch is a critical safety mechanism that aids in preventing fires and carbon monoxide. You shouldn’t seek to repair this problem on your own.
  3. An individual light is flashing quickly and the other is flashing slowly. This usually means power polarity has been inverted. Your heating system might have a wiring problem that needs expert support from Central Heating & Plumbing.
  4. Both lights are flashing slowly. This signifies your furnace’s blower motor likely isn’t working. This piece circulates hot air from the furnace into your home. We can help in figuring out what’s causing a problem with this component.
  5. An individual light is flashing slowly and the other is flashing rapidly. This signifies your HVAC system could have low voltage or a short circuit. Get in touch with our experts at 724-401-1843 for support.
  6. One light is flashing on, on and off while the other blinks on, off, on. This signifies there could be trouble with your heater’s motherboard or wiring. Central Heating & Plumbing can locate the error and fix it.
  7. The pair of lights are using every other slow flashes. This indicates your furnace possibly has a flame error. There could be an issue with its gas supply, gas valve or ignitor control. Call us at 724-401-1843 for support.
  8. One light flickers slowly while the other is solid. This usually signifies your HVAC system’s limit switch is open. The switch stops your heater from getting too hot. Reach out to the specialists at Central Heating & Plumbing for help.

Heater Blower Works But No Warm Air

Here’s what could be at fault when you observe your heater’s blower fan running, but you aren’t gaining any heat.

  • Both lights are giving alternating fast flickers. This indicates your furnace ignitor might not be working. This piece kindles gas in your heater to produce warmth and should be fixed by an expert from Central Heating & Plumbing.

Turn to Us for Expert Furnace Repair

When you need to get your furnace fixed quickly, trust the technicians at Central Heating & Plumbing. Our pros will handle the problem without delay and have your space feeling cozy again in no time. Get in touch with us at 724-401-1843 or contact us online to schedule an appointment today.

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