So I have 4 dogs, 2 cats, and 2 guinea pigs in our two story house. Soooo, we have a lot of hair and dust flying around. So 2 questions:

1) Our intake vents don't have filters or room to put filters in. Would it be recommended to replace them with ones I can filter, or how would you recommend I help control the dander and dust? We are using a hepa box filter for the unit.

2) Our house is 2 stories, and has a split ducting system. The problem I'm having is it sounds like a damn freight train when it kicks on upstairs. Is this something that can be fixed? A/c tech I had come out told me to just get used to it in a split duct setup, but I wanted a second opinion.

Thabks!