1. Apply a ¼" wide bead of high temperature silicone all around the boiler vent connection 1" from the end. Install 5" to 4" reducer on boiler vent connection. Secure properly with a clamp. 2. Install 4" galvanized vent pipe (maximum of 6 ft) and 90º elbows (maximum of 2) as needed. Apply high temperature silicone at all pipe joints and screw heads. Make sure all joints are sealed hermetically. IMPORTANT NOTICES Once the entire venting system is installed, make sure all joints are secure. All seams and joints of the exhaust venting must be checked for gas tightness. High temperature tape or high temperature silicone sealant can be used to ensure an airtight venting system. It is required to have the entire system checked and serviced by a qualified technician at least once annually following initial installation. Installation Procedure for Air Intake Terminal and Inlet Air Pipe 1. Cut properly sized opening in the outside wall and install the 4" air intake hood. (Applies only when the Aerocowl termination is used. Caulk as needed.