We have just moved into a project house. It's very damp and the carpets are old! We're going to rip it out and replace them a little later. We're working on sorting the damp issues as well, but in the meantime everything's quite smelly. What can I do to make it smell a bit fresher? Plug ins? Anything else? I don't want anything overpowering, just something fresh smelling. Thank you.