Furnace troubleshooting

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

While your Lennox® heater isn’t able to talk to you, it possesses a method to tell you about a furnace error.

Its control panel has a set of LED lights that can display a fault code. Depending on the problem, your heating system might display continuous or flashing lights.

Although there are some elementary heating fixes you can do without an expert, most services are best taken care of by HVAC technicians. When your heating system won’t turn on or provide heat, contact Ilten's Incorporated at 319-208-3295 for experienced furnace repair in Cedar Rapids.

Our specialists will quickly detect and repair the issue, even if you don’t have a Lennox heater. We can fix any brands or makes—and get the comfort returned to your residence without delay.


What Does the Flashing Light on My Heater Mean?

Your heating system depends on lights to flash code when it needs to be repaired. It also uses these lights to tell you it’s working correctly.

Regular operation involves:

  • Concurrent slow flash—heating system running properly.
  • Concurrent fast flash—heater is starting to call for heat.

If you see a single light going on and off slowly and the other flashing fast, your heating system might have a low flame signal. This can happen even when your heater is working correctly. It signifies the flame sensing rod could have build-up or in the wrong area on the burner. Call us at 319-208-3295 for assistance.

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

Heating System Refuses to Kick On

Here are many of the light patterns you might notice when your heater refuses to or stay on. The majority of these problems need to be fixed by a specialist, for instance from Ilten's Incorporated.

  1. Both LED lights are off. This indicates your furnace might not have electricity. Check the breaker box to make sure the heating system fuse has not triggered. Try resetting the fuse if it has moved into the “off” position. If it promptly flips after a subsequent reset, don’t try to reset it again and get in touch with us us at 319-208-3295.
  2. One light is unchanging and the other is flickering slowly. This implies the flame rollout switch is possibly not working right. The part is a critical safety tool that helps in stopping fires and carbon monoxide. You shouldn’t seek to handle this malfunction without professional help.
  3. A single light is flashing rapidly and the other is flashing slowly. This likely indicates power polarity has been inverted. Your heating system might have a wiring error that needs professional aid from Ilten's Incorporated.
  4. The pair of lights are flashing slowly. This means your heating system’s blower motor probably isn’t running. This piece moves heated air from the HVAC system into your residence. We can help in determining what’s causing a problem with this piece.
  5. An individual light is flickering slowly and the other is blinking rapidly. This means your heater may have insufficient voltage or a short circuit. Call our technicians at 319-208-3295 for support.
  6. One light is flickering on, on and off while the other flickers on, off, on. This means there might be trouble with your heating system’s control panel or wiring. Ilten's Incorporated can locate the problem and repair it.
  7. Both lights show every other slow flashes. This indicates your HVAC system possibly has a flame failure. There might be a problem with its gas supply, gas valve or ignitor control. Contact us at 319-208-3295 for assistance.
  8. An individual light flashes slowly while the other is continuous. This usually indicates your furnace’s limit switch is malfunctioning. The switch stops your heater from becoming too warm. Get in touch with the pros at Ilten's Incorporated for assistance.

Heating System Blower Runs But No Warmth

Here’s what may be broken when you notice your furnace’s blower fan on, but you aren’t gaining any heated air.

  • Both lights are giving alternate quick flickers. This indicates your furnace ignitor could be broken. This part kindles energy in your heating system to make heat and should be serviced by a technician from Ilten's Incorporated.

Trust Us for Skilled Furnace Repair

When you need to have your furnace in working order quickly, depend on the experts at Ilten's Incorporated. Our techs will fix the problem quickly and have your house feeling relaxing again in no time. Get in touch with us at 319-208-3295 or contact us online to schedule an appointment today.

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