Black & Decker BSAH1215AC Instruction Manual page 18

INSTALLATION INSTRUCTIONS
5. Drill a 3 in. (7.6 cm) hole through the wall so you can feed
the refrigerant lines and condensate drain hose outside.
• Make a mark in the center of the hole in the mounting plate. Use a
keyhole saw or a drill with a hole-cutting attachment to create a
circular 3 in. (7.6 cm) opening through the wall that slopes slightly
downward toward the ground to ensure adequate drainage.
WARNING - Make sure there are no pipes or wires behind the wall
before drilling or cutting the hole.
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