Yes, split-type air conditioner installation almost always requires drilling at least one hole through the wall, typically around 65 to 75 millimeters in diameter, to allow the refrigerant lines, drainage pipe, and electrical cable to pass from the indoor unit to the outdoor condenser. The exact number and placement of holes depend on the layout of the room and the distance between the two units. Window-type air conditioners do not require drilling in the same way, as they are designed to fit into an existing window opening or a pre-cut wall sleeve, though some installations may still involve minor modifications to ensure a proper fit and seal.