Lennox 66P86 – Selkirk AF35-55 Aluminum Flexible Chimney Liner Kit is an OEM HVAC venting solution designed to restore and improve chimney performance for gas-fired furnaces, boilers, and other approved heating appliances. This kit features a 5.5 inch diameter aluminum flexible liner with a total length of 35 feet, allowing it to adapt easily to offsets, bends, and irregular chimney paths during installation.

Manufactured by Selkirk, this aluminum flex liner kit is engineered to enhance draft efficiency, reduce condensation issues, and protect masonry chimneys from corrosion caused by combustion byproducts. The lightweight yet durable aluminum construction makes handling and installation easier while maintaining long-term reliability in residential and light commercial HVAC applications.

This chimney liner kit is commonly used during system upgrades, appliance replacements, or chimney relining projects where proper venting is required to meet safety and performance standards. As a genuine OEM-compatible component, Lennox 66P86 ensures proper fit and dependable operation when installed according to manufacturer and local code requirements.

Product features and benefits:

• 5.5 inch diameter aluminum flexible chimney liner
• 35 foot total length for extended chimney runs
• Flexible design allows installation through offsets and bends
• Improves draft performance and venting efficiency
• Helps protect chimney structure from moisture and corrosion
• Suitable for gas-fired furnaces and boiler applications
• Manufactured by Selkirk for OEM-quality performance

Typical applications:

• Chimney relining for gas furnaces and boilers
• HVAC system replacements and upgrades
• Residential and light commercial venting installations
• Restoring code-compliant chimney venting performance

Lennox 66P86 – Selkirk AF35-55 Aluminum Flexible Chimney Liner Kit is a reliable HVAC venting component designed to support safe exhaust flow, improve system efficiency, and extend the service life of existing chimneys. Ideal for contractors and homeowners seeking an OEM-grade chimney liner solution optimized for performance and durability.