Furnace troubleshooting

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

While your Lennox® furnace isn’t able to speak to you, it has a process to get your attention when there’s a furnace error.

Its control board has a set of LED lights that can show a fault code. Based on the failure, your heating system may use continuous or flashing lights.

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

Our technicians will speedily discover and repair the malfunction, even if you don’t own a Lennox heating system. We can fix whichever types or configuration—and get the comfort returned to your house quickly.


What Does the Flashing Light on My Heater Mean?

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

Regular function includes:

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

If you see a lone light blinking slowly and the other flashing rapidly, your heating system could have a low flame signal. This can happen even when your heater is working correctly. It signifies the flame sensing rod may be dirty or in the bad spot on the burner. Contact us at 507-218-0088 for assistance.

Here are some of the most common problems for Lennox heaters.

Heater Will Not Start

Here are many of the light arrangements you might observe when your heat will not 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 aren’t lit. This signifies your heater might not be receiving power. Look at the breaker box to make sure the heater fuse has not tripped. You should reset the fuse if it has moved into the “off” spot. If it promptly 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 flickering slowly. This signifies the flame rollout switch is may be open. The switch is an important safety device that assists in preventing fires and carbon monoxide. You shouldn’t attempt to repair this malfunction on your own.
  3. A single light is flickering fast and the other is flickering slowly. This typically means power polarity has been reversed. Your furnace might have a wiring problem that requires specialized assistance from Brogan Heating & AC Inc.
  4. Both lights are flashing slowly. This means your heating system’s blower motor likely isn’t working. This piece circulates warm air from the heater into your residence. We can help in pinpointing what’s wrong with this part.
  5. An individual light is flickering slowly and the other is flashing fast. This signifies your heater could have not enough voltage or a short circuit. Contact our specialists at 507-218-0088 for support.
  6. One light is blinking on, on and off while the other blinks on, off, on. This signifies there may be an issue with your furnace’s control panel or wiring. Brogan Heating & AC Inc can find the issue and fix it.
  7. Both lights display alternating slow flickers. This means your HVAC equipment may have a flame issue. There may be a problem with its gas supply, gas valve or ignitor control. Get in touch with us at 507-218-0088 for help.
  8. A single light blinks slowly while the other stays solid. This often means your furnace’s limit switch is experiencing an error. The switch keeps your furnace from getting too hot. Contact the professionals at Brogan Heating & AC Inc for help.

Heater Blower Works But No Warm Air

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

  • Both lights are giving alternating fast flashes. This means your furnace ignitor might be broken. This component ignites gas in your furnace to create warm air and should be fixed by a specialist from Brogan Heating & AC Inc.

Turn to Us for Professional Furnace Repair

When you have to have your furnace repaired without delay, depend on the specialists 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 now.

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