We have a problem with a weird smell that comes and goes in a bedroom in a brand new house. It's the smell of puke! It doesn't smell musty at all. It comes and goes all the time every day, sometimes for hours. The carpets have been removed and there's nothing underneath. The carpets have been professionally cleaned, but the puke smell still comes and goes. I've heard of bad wiring/electrical causing weird smells but I haven't checked the lights yet. It would really surprise me cause the lights are pretty much never on in that bedroom. There's a bathroom just on the other side of the room, I've checked the plumbing and nothing seems to be leaking (and again, it doesn't smell musty). Anyone got ideas?

Any chance a child puked into the heating air duct? It would come and go as the furnace operates

Does the smell appear when you use the bathroom, I am wondering if the plumber used a cheater vent and terminated it in the wall cavity between the bath and bedroom.

Sewer gas does not smell anything like puke.