Furnace troubleshooting

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

While your Lennox® heater can’t chat with you, it has a way to tell you about a furnace error.

Its motherboard has a set of LED lights that can show a fault code. Depending on the failure, your heater could use solid or flashing lights.

Although there are a few simple furnace fixes you can do without an expert, many repairs are best left to HVAC technicians. When your furnace will not start or give warm air, get in touch with Cytech Heating & Cooling at 956-630-3522 for professional furnace repair in Edinburg.

Our experts will quickly spot and handle the fault, even if you don’t own a Lennox furnace. We can repair any kinds or makes—and get the warmth restored to your house without delay.


What Does the Flashing Light on My Furnace Mean?

Your heater uses lights to flash code when it isn’t working right. It also works this setup to relay it’s working properly.

Normal heating involves:

  • Simultaneous slow flash—furnace running properly.
  • Both lights flash fast—heating system is beginning to call for heat.

If you see one light flashing slowly and the other going on and off rapidly, your furnace may be experiencing a low flame signal. This can take place even when your heater is operating correctly. It signifies the flame sensing rod could need to be cleaned or in the incorrect spot on the burner. Call us at 956-630-3522 for assistance.

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

Heater Will Not Start

Here are a few of the light arrangements you may see when your heater won’t turn on or keep heating. Most of these problems need to be fixed by a professional, such as one from Cytech Heating & Cooling.

  1. The duo of LED lights are extinguished. This signifies your HVAC system might not have electricity. Find the breaker box to ensure the heating system fuse isn’t flipped. You should reset the fuse if it has moved into the “off” spot. If it immediately flips after a subsequent reset, don’t touch the breaker and call us at 956-630-3522.
  2. A single light is unchanging and the other is blinking slowly. This signifies the flame rollout switch is likely not working right. The component is an important safety guard that helps in avoiding fires and carbon monoxide. You shouldn’t seek to fix this malfunction on your own.
  3. A single light is flashing fast and the other is flashing slowly. This usually signifies power polarity has been inverted. Your furnace might have a wiring issue that calls for expert aid from Cytech Heating & Cooling.
  4. The duo of lights are blinking slowly. This means your heater’s blower motor probably isn’t working. This component circulates heated air from the HVAC system into your residence. We can assist in figuring out what’s causing an issue with this part.
  5. A single light is flashing slowly and the other is flashing fast. This means your HVAC system might have not enough voltage or a short circuit. Call our specialists at 956-630-3522 for support.
  6. One light is flickering on, on and off while the other flashes on, off, on. This signifies there may be a problem with your heating system’s motherboard or wiring. Cytech Heating & Cooling can find the issue and take care of it.
  7. The pair of lights are using alternate slow flickers. This signifies your furnace may have a flame error. There may be an issue with its gas supply, gas valve or ignitor control. Contact us at 956-630-3522 for help.
  8. An individual light flickers slowly while the other remains continuous. This typically signifies your heating system’s limit switch is malfunctioning. The switch prevents your HVAC equipment from becoming too warm. Get in touch with the pros at Cytech Heating & Cooling for assistance.

Heater Blower Operates But No Heat

Here’s what might be wrong when you notice your heating equipment’s blower fan working, but you aren’t gaining any heated air.

  • Both lights display every other quick flickers. This signifies your furnace ignitor might not be in working order. This component ignites gas in your heater to produce warmth and should be fixed by a technician from Cytech Heating & Cooling.

Depend on Us for Expert Furnace Repair

When you have to get your furnace repaired quickly, trust the technicians at Cytech Heating & Cooling. Our techs will repair the fault promptly and have your space feeling comfortable again in no time. Get in touch with us at 956-630-3522 or contact us online to schedule an appointment today.

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