Whole house dehumidifier – where to install?
I am currently building a 2 story, 5400 sq ft home in Alabama where humidity is often high. We will install a whole house dehumidifier (“WHD”) as part of the HVAC system. We will have 3 HVAC units (2 and 3 ton down, 2 ton up with variable speed air handlers and 2 stage compressors). The installer is proposing to install one WHD (for entire house) on the larger of the downstairs unit which is also the unit that will control the kitchen and great room areas. The master bedroom/bath and another downstairs bedroom/bath will be on the other HVAC unit (no dehumidifier). No dehumidifier proposed for upstairs.
Question: Does it matter on which unit the WHD is attached to? Should it be upstairs or downstairs? Is one WHD sufficient to control the entire house? Does the humid air rise upstairs and into attic (spray foamed) and if so, does it need to be controlled?