This adaptor kit is designed for Lennox HVAC systems that require a transition from rectangular/square duct openings on the unit to a standard 14-inch round duct connection. It allows installers to connect round ductwork (such as flexible or rigid round ducts) to the supply or return openings on compatible Lennox packaged units or air handlers.

 

Key Features:

• Transitions two typical square outlet sizes — **18.5" x 14.5" and 18.5" x 17.25" — to a 14" round duct connection.
• Made from durable galvanized sheet metal for strength and corrosion resistance.
• Enables a smooth airflow transition with minimal leakage when properly installed.
• Designed specifically for Lennox heating and cooling equipment requiring this type of duct conversion.
• Ideal for both new installations and retrofit applications where square to round conversion is needed.

 

Use Case:

This adaptor kit is commonly used on rooftop packaged units or air handlers where the factory opening is rectangular, but the duct system is round. It simplifies connecting standard round ducts to the unit, improving airflow and sealing.

Installation Notes:

Install with sheet metal screws and HVAC sealant to ensure a secure, airtight connection. Make sure the round collar is aligned so that the connected ductwork has minimal bends immediately after the adaptor for optimal airflow.