Hi all. Recently we had a new furnace and air conditioner installed. Works great - no problems there. However, when the AC comes on - I can smell an odor which I believe is coming from the upstairs. (We live in an up and down, with a tenant upstairs). Each time the AC comes on I swear I can smell a combination of wet dog and garbage. My husband thinks I'm imagining things, but I really don't think so. So my question is: is this at all possible, or am I truly a nutbar? Any suggestions you can give would be appreciated.