Furnace troubleshooting

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

While your Lennox® furnace can’t speak to you, it has a procedure to communicate a furnace error.

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

Though there are various basic heating adjustments you can do without an expert, the majority of services are best taken care of by experts. When your heater won’t turn on or deliver warm air, get in touch with James Heating & A/C, Inc at 336-853-6070 for professional furnace repair in Lexington.

Our specialists will swiftly spot and handle the fault, even if you don’t own a Lennox heater. We can fix whichever brands or configuration—and get the comfort reintroduced to your house quickly.


What Does the Flashing Light on My Heater Mean?

Your furnace relies on lights to flash code when it needs to be repaired. It also engages this system to tell you it’s running properly.

Normal operation includes:

  • Concurrent slow flash—heating system running like it should.
  • Both lights flash fast—heating system is initiating the call for heat.

If you realize that a solitary light going on and off slowly and the other flashing rapidly, your heating system could have a low flame signal. This can happen even when your heater is heating properly. It signifies the flame sensing rod might be dirty or in the incorrect area on the burner. Call us at 336-853-6070 for assistance.

Here are some of the most routine issues for Lennox heating systems.

Heater Refuses to Start

Here are a few of the light patterns you might see when your heat will not or keep running. Most of these problems must be repaired by a professional, for instance from James Heating & A/C, Inc.

  1. Both LED lights are extinguished. This indicates your heating system might not have power. Examine the breaker box to confirm the furnace fuse has not triggered. You should reset the fuse if it has moved into the “off” position. If it promptly turns off after a subsequent reset, don’t touch the breaker and get in touch with us us at 336-853-6070.
  2. A single light is unchanging and the other is blinking slowly. This shows the flame rollout switch is likely not working right. The component is an essential safety guard that assists in stopping fires and carbon monoxide. You shouldn’t try to repair this issue yourself.
  3. An individual light is blinking fast and the other is blinking slowly. This often indicates power polarity has been reversed. Your furnace might have a wiring fault that calls for specialized aid from James Heating & A/C, Inc.
  4. Both lights are flickering slowly. This means your heating system’s blower motor likely isn’t running. This piece circulates warm air from the heating system into your house. We can assist in figuring out what’s causing an issue with this piece.
  5. A single light is blinking slowly and the other is flickering rapidly. This signifies your heating system might have insufficient voltage or a short circuit. Reach out to our specialists at 336-853-6070 for assistance.
  6. One light is flickering on, on and off while the other flickers on, off, on. This signifies there could be a malfunction with your heater’s control board or wiring. James Heating & A/C, Inc can determine the problem and repair it.
  7. Both lights show alternating slow flashes. This means your HVAC system possibly has a flame issue. There might be a problem with its gas supply, gas valve or ignitor control. Contact us at 336-853-6070 for assistance.
  8. A single light flashes slowly while the other stays steady. This usually signifies your heating system’s limit switch is malfunctioning. The switch stops your heater from overheating. Reach out to the pros at James Heating & A/C, Inc for support.

Heater Blower Works But No Warmth

Here’s what might be broken when you hear your heating system’s blower fan running, but you aren’t receiving any warm air.

  • Both lights are giving alternate quick flashes. This indicates your furnace ignitor may be broken. This component ignites energy in your heating system to make heat and should be fixed by an expert from James Heating & A/C, Inc.

Depend on Us for Expert Furnace Repair

When you have to get your heater repaired quickly, turn to the technicians at James Heating & A/C, Inc. Our pros will repair the fault right away and have your residence feeling relaxing again soon. Call us at 336-853-6070 or contact us online to schedule an appointment right away.

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