Furnace troubleshooting

Top Lennox® Furnace Error Codes (and What They Mean)

While your Lennox® heater isn’t able to speak to you, it has a way to communicate a furnace error.

Its motherboard has double LED lights that can show a fault code. Depending on the issue, your heater may display continuous or flashing lights.

Although there are a few simple HVAC fixes you can finish without an expert, the majority of tasks are best handled by experts. When your heating system refuses to start or give warm air, contact Select Comfort System Heating & Air Conditioning at 801-305-4777 for experienced furnace repair in West Valley City.

Our technicians will quickly detect and repair the fault, even if you don’t use a Lennox furnace. We can service whichever types or configuration—and get the heat returned to your residence without delay.


What Does the Flashing Light on My Heater Mean?

Your heater uses lights to flash code when it requires repairs. It also engages this setup to let you know it’s operating like it should.

Correct heating consists of:

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

If you notice a solitary light flashing slowly and the other blinking fast, your heating system could be having a low flame signal. This can take place even when your furnace is running correctly. It means the flame sensing rod might be dirty or in the wrong spot on the burner. Contact us at 801-305-4777 for help.

Here are some of the most typical faults for Lennox furnaces.

Heating System Will Not Turn On

Here are many of the light patterns you might see when your heat will not or stay on. The majority of these errors have to be handled by a specialist, for instance from Select Comfort System Heating & Air Conditioning.

  1. The pair of LED lights aren’t lit. This means your heating system might not have electricity. Examine the breaker box to confirm the heater fuse hasn’t triggered. You should reset the fuse if it has moved into the “off” spot. If it promptly turns off following a reset, don’t touch the breaker and call us at 801-305-4777.
  2. A single light is continuous and the other is blinking slowly. This implies the flame rollout switch is may be malfunctioning. The part is a critical safety guard that assists in preventing fires and carbon monoxide. You shouldn’t seek to handle this issue yourself.
  3. One light is flickering rapidly and the other is blinking slowly. This typically signifies power polarity has been reversed. Your heating system may have a wiring problem that needs expert aid from Select Comfort System Heating & Air Conditioning.
  4. Both lights are blinking slowly. This means your furnace’s blower motor likely isn’t operating. This piece sends warm air from the furnace into your house. We can aid in determining what’s causing a problem with this component.
  5. One light is flickering slowly and the other is flickering rapidly. This means your HVAC system may have low voltage or a short circuit. Reach out to our professionals at 801-305-4777 for support.
  6. One light is flickering on, on and off while the other blinks on, off, on. This means there could be trouble with your heater’s control board or wiring. Select Comfort System Heating & Air Conditioning can locate the fault and take care of it.
  7. The duo of lights display every other slow flashes. This means your HVAC equipment possibly has a flame failure. There may be a problem with its gas supply, gas valve or ignitor control. Call us at 801-305-4777 for help.
  8. An individual light flickers slowly while the other stays steady. This often indicates your HVAC equipment’s limit switch is experiencing an error. The switch keeps your heater from becoming too warm. Reach out to the experts at Select Comfort System Heating & Air Conditioning for support.

Furnace Blower Operates But No Warmth

Here’s what might be at fault when you observe your heater’s blower fan running, but you aren’t getting any warmth.

  • The duo of lights display every other rapid flashes. This indicates your furnace ignitor might not be in working order. This part ignites energy in your heater to produce warm air and should be fixed by an expert from Select Comfort System Heating & Air Conditioning.

Depend on Us for Professional Furnace Repair

When you need to get your heating system fixed fast, depend on the technicians at Select Comfort System Heating & Air Conditioning. Our technicians will handle the issue quickly and have your home feeling comfortable again in no time. Reach out to us at 801-305-4777 or contact us online to schedule an appointment right away.

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