Lennox Furnace Error Code E206

E206 means the furnace has detected a mismatch between the indoor blower motor's horsepower rating and what the unit's capacity requires. This is typically a configuration or installation issue. The furnace control board compares the motor's characteristics against the selected unit size code, and when they do not align, it flags the error. A technician should first verify that the correct unit size code is configured per the installation instructions.

A motor mismatch can mean the blower is not moving the correct volume of air through the heat exchanger, which can lead to overheating or reduced system efficiency. It is not advisable to continue running the furnace in this condition for extended periods. Have the issue diagnosed and corrected before relying on the unit for normal heating operation.

If the fix is a configuration correction with no parts needed, costs are limited to a service call fee, typically in the range of $75 to $150 depending on your location. If a blower motor replacement is required, total costs including parts and labor generally range from $300 to $700 or more depending on the specific motor and your area. A motor control module replacement falls in a similar range. Getting a diagnostic assessment from a certified technician first will clarify exactly what is needed.

In some cases, the fix is as straightforward as correcting an incorrect size code in the furnace configuration settings, which a knowledgeable DIYer comfortable with following Lennox installation guides could attempt. However, if the issue involves a wrong or failed blower motor or motor control module, a qualified HVAC technician is needed to correctly identify and replace the component. Incorrectly sizing or installing a blower motor affects system airflow and efficiency, so professional verification is strongly recommended.

A simple reset may temporarily clear the error code, but it will return if the underlying cause has not been addressed. If the unit size code is incorrect or the installed motor does not match the required horsepower, the control board will detect the mismatch again after restarting. The root cause must be corrected for the fault to be permanently resolved.