I'd like to get feedback on the following design for my basement:
My basement is about 2500sqft with drop down ceiling. Summer months RH is 60% and I wish to bring this down to 45%.
I installed an Aprilaire 1720 an it is over working. Howver, it almost never shuts off. Therefore, I also bought a Ultra-Aire XT150. I also have a Panasonic WhisperLine™ 440 CFM In-Line Fan.
I have 2x2 open grills in the drop down ceiling so I can easily draw air in without dedicated vents.
I am considering 8" tapping the Panasonic into the existing ductwork so that the WhisperLine™ 440 CFM In-Line Fan exhausts air outside every few hours on a timer. I will install a normally closed damper between the Panasonic and the HVAC ductwork so that this only opens with the Panasonic on, drawing air from the duct vents already installed in the ceiling. Will the negative pressure consequence in the basement here be a good thing, drawing dryer air from the upper floor?
Install Aprilaire 1720 with its inlet coming from a 8"T above the drop ceiling and its outlet ducted to a 8"T to above the kitchen
Install UA XT150 with its own return via a 10"T on the other far side of the basement and tap the supply side of UA to the HVAC ducting. I would also install a 6" fresh air to the UA as well.
Your suggestions and feedback would be appreciated.