Install the water heater vent hood according to the manufacturer's instructions for your water heater. Most vent hoods have three legs that fit into notches on the top of the water heater.
Insert the end of the B vent pipe into the top of of the vent hood sleeve. Twist the vent pipe clockwise one-quarter turn to lock it in place. There are protruding tabs on the outside lip of the B vent pipe that match the recessed notches inside the vent hood sleeve.
Place the B vent clamp on a flat surface with the inside of the clamp facing you. Attach the self-adhesive grommet strips on the metal strip of the clamp at the top and bottom.
Pick up the B vent clamp and bend it around the seam between the B vent pipe and the vent hood. The clamp has two angled ends with screw holes. Press the angled ends together and secure the clamp with machine screws and the Phillips screwdriver.