Under what condition should casing extension boots be installed?

Casing extension boots should be installed if they are explicitly listed as part of the appliance. This means that the installation of these components is not merely a matter of preference, but rather a requirement defined by the manufacturer's specifications. Following these specifications ensures that the appliance operates as intended, providing proper airflow, efficiency, and adherence to safety standards.

When an appliance specifies the use of casing extension boots, it typically indicates that certain design aspects of the unit rely on their inclusion for optimal performance. This may apply to factors like airflow dynamics, insulation, and clearance requirements, which are critical for effective operation.

While factors such as available space and local codes can influence installation decisions, they don't override the manufacturer's guidelines. If the appliance has particular requirements for casing extensions and those are not adhered to, it could lead to suboptimal performance or even violations of safety regulations, making adherence to the listing essential.