I have an old home that has been in my husband's family for years. No matter how well I clean it or deodorize it, the house still has a smell. When the new vents were added through the ceiling, no one removed the old vents from the floor. I have often wondered if this had something to do with the odor. We have also had mice in the past. I love our old house, but I would like for it to smell as fresh as I keep it clean. Should the old vents be removed? , if so, by who?