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 communicate a furnace error.

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

Although there are a few elementary heating fixes you can complete on your own, most fixes are best left to the professionals. When your heating system won’t start or deliver heated air, call Brogan Heating & AC Inc at 507-218-0088 for skilled furnace repair in Rochester.

Our technicians will speedily identify and repair the malfunction, even if you don’t own a Lennox heater. We can fix all types or configuration—and get the comfort reintroduced to your house without delay.


What Does the Flickering Light on My Heating System Mean?

Your heater uses lights to flash code when it needs to be repaired. It also engages this setup to let you know it’s operating correctly.

Correct heating includes:

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

If you see a lone light blinking slowly and the other flashing fast, your heater might be experiencing a low flame signal. This can happen even when your heater is working correctly. It indicates the flame sensing rod may be dirty or in the bad spot on the burner. Contact us at 507-218-0088 for help.

Here are several other of the most common problems for Lennox heaters.

Heating System Will Not Start

Here are many of the light arrangements you could observe when your heat refuses to or keep heating. The majority of these errors must be taken care of by a specialist, such as one from Brogan Heating & AC Inc.

  1. Both LED lights are extinguished. This means your heater might not be receiving power. Look at the breaker box to make sure the heating system fuse has not tripped. You should reset the fuse if it has moved into the “off” area. If it immediately trips following a reset, don’t try to reset it again and contact us at 507-218-0088.
  2. An individual light is solid and the other is blinking slowly. This signifies the flame rollout switch is may be open. The switch is an important safety device that aids in preventing fires and carbon monoxide. You shouldn’t try to repair this problem without professional help.
  3. A single light is flickering rapidly and the other is flickering slowly. This usually means power polarity has been reversed. Your furnace might have a wiring problem that requires expert assistance from Brogan Heating & AC Inc.
  4. The pair of lights are flashing slowly. This means your heater’s blower motor likely isn’t working. This component moves warm air from the furnace into your residence. We can help in figuring out what’s wrong with this part.
  5. An individual light is flickering slowly and the other is flashing fast. This indicates your heater might have insufficient voltage or a short circuit. Contact our specialists at 507-218-0088 for assistance.
  6. One light is flickering on, on and off while the other blinks on, off, on. This indicates there may be a problem with your furnace’s control panel or wiring. Brogan Heating & AC Inc can find the fault and fix it.
  7. Both lights are using alternating slow flickers. This means your HVAC equipment may have a flame failure. There might be a problem with its gas supply, gas valve or ignitor control. Get in touch with us at 507-218-0088 for help.
  8. An individual light blinks slowly while the other remains solid. This often means your furnace’s limit switch is experiencing an error. The switch keeps your HVAC system from getting too hot. Get in touch with the professionals at Brogan Heating & AC Inc for support.

Heating System Blower Works But No Warm Air

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

  • Both lights are giving alternating fast flashes. This means your furnace ignitor might not be working. This piece ignites gas in your heating system to create warmth and should be repaired by a specialist from Brogan Heating & AC Inc.

Turn to Us for Skilled Furnace Repair

When you have to have your furnace in working order fast, depend on the professionals at Brogan Heating & AC Inc. Our technicians will repair the fault without delay and have your rooms feeling comfortable again in no time. Contact us at 507-218-0088 or contact us online to request an appointment right away.

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