Lennox Furnace Error E266 / E267: Rollout Switch Tripped
When the control board of your Lennox furnace displays error E266 / E267, it means the flame rollout safety switch opened due to abnormal combustion. Understanding these codes helps our technicians arrive prepared with the right diagnostic approach and parts. BC Wide Home Services Ltd, doing business as BC Wide Heating & Air Conditioning serves Greater Vancouver homeowners with Lennox-specific expertise and a commitment to accurate, efficient service.
Cost to Fix Lennox Error E266 / E267
The cost to resolve error E266 / E267 on your Lennox furnace depends on the root cause. Simple fixes like cleaning a flame sensor or replacing a capacitor are relatively affordable. More involved repairs such as gas valve replacement, control board replacement, or heat exchanger service will be more significant. BC Wide Home Services Ltd, doing business as BC Wide Heating & Air Conditioning provides a detailed diagnosis and written estimate before any work begins, so you can make an informed decision about the repair.
Preventing Lennox Error E266 / E267 in the Future
Regular maintenance is the best way to prevent error E266 / E267 and other fault codes on your Lennox system. Annual professional maintenance includes cleaning the flame sensor, inspecting wiring connections, checking gas pressure, verifying proper airflow, and testing all safety controls. BC Wide Home Services Ltd, doing business as BC Wide Heating & Air Conditioning offers comprehensive maintenance programs for Lennox equipment. Well-maintained systems have fewer error codes and emergency service calls.
What Error E266 / E267 Means on Your Lennox Furnace
Error E266 / E267 on Lennox furnace systems indicates the flame rollout safety switch opened due to abnormal combustion. This diagnostic code is generated by the system's control board when sensor readings or operating conditions fall outside the expected range. Lennox equipment uses sophisticated diagnostics to help technicians pinpoint problems accurately. The error code is stored in the control board's memory and can be retrieved even after the system has been reset.
Common Causes of Lennox Error E266 / E267
Error E266 / E267 on Lennox equipment can be caused by several factors. The most common causes include: blocked heat exchanger, inadequate combustion air, excessive gas pressure, cracked heat exchanger. BC Wide Home Services Ltd, doing business as BC Wide Heating & Air Conditioning technicians systematically test each potential cause to identify the root issue efficiently. The specific cause in your situation will depend on your system's model, installation configuration, and operating history.
How to Respond to Lennox Error E266 / E267
When you see error E266 / E267 on your Lennox system, start with these steps: Check that the power supply is on and stable. Verify the gas supply valve is open if applicable. A tripped rollout switch is a serious safety concern. Turn off the furnace and call a technician immediately. If the error persists or returns after resetting the system, professional diagnosis is recommended. Do not repeatedly reset the system without addressing the underlying cause, as this can lead to component damage or safety hazards.
Safety Reminder
If you smell gas, suspect carbon monoxide or believe there is an immediate danger, leave the property and contact emergency services or the appropriate gas emergency authority. Do not remain inside — exit the building immediately and call for help from outside.