The Aprilaire 4522 Basement Kit allows the Aprilaire 1700 - Series Dehumidifier to automatically switch between whole-home and localized dehumidification. Automatic switching allows the Aprilaire 1700 - Series Dehumidifier to provide dehumidification to the entire home when the air-conditioning is on and, then switches to a specific location such as a basement when the air conditioning is turned off.

This kit works for both finished basements and unfinished basements. Finished basements only call for (1) pair of dampers to be used, while unfinished basements require both pairs to be used.