Bradford White THROUGH-THE-WALL GAS WATER HEATER Install And Operation Instructions page 14

THROUGH THE WALL VENTING:
Cut a 3 1/2 in. (8.9 cm) diameter hole in the wall at the point where the vent
connector is going to pass through the wall. Use the proper cement to secure
the 90° vent terminal provided with the water heater to the vent connector. The
distance between the edge of the 90° vent terminal and the exterior wall (see
Figure 3) must be 1 in. (2.5 cm). Use the proper cement and assembly
procedures to secure the vent connector joints between the terminal and the
blower outlet. Provide support brackets for every 3 feet (.91 m) of horizontal vent.
Figure 3
Venting (Part I) continued-
THROUGH THE ROOF VENTING: (VERTICAL VENTING)
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