What do you need to pay attention to at the central air conditioning access opening? (1), the central air conditioning access port size is generally 400mm*400mm, access port material had better use ABS material. Traditional aluminum alloys need to be welded, while gypsum materials are hard, fragile, bulky and inconvenient to install. ABS material has good flexibility, long service life, no deformation, removable and washable, so it is very suitable to be used as a manhole material. ② The access opening of central air conditioning is generally located on the left side of the air outlet or just below the electrical box. If the size of the air return opening is sufficient, the air return opening can also be used as an access opening, so there is no need to leave an access opening. The access opening is not limited to one position, but should be designed according to the actual situation. ③ Under normal circumstances, the access opening needs to be sealed invisibly, and if the return air outlet is also used as the access opening, there is no need to seal it. ④ The maintenance opening shall be reserved by the decorator, and the air-conditioning construction unit shall be responsible for installing and sealing the filter screen. The air-conditioning construction unit shall pay attention to whether the reserved opening of the decorator meets the requirements. ⑤ It is best not to put tall objects that hinder maintenance under the access opening, such as wardrobes and bookshelves.