At the weekend we lit our log burning stove downstairs for the first time since late spring. A damp patch appeared on the bedroom wall above the room, just above the skirting board and about in line where the chimney is, what could this damp be? It has dried out but has left a satin on the wall paper. The stove has only been in a couple of years and from what i gather by the previous owners of the house has not caused problems before?

That shouls be stain on the bedroom wall not satin sorry

Just to clarify is this a wood stove or gas stove?