Large black ant (harmless) or carpenter ant?
It is difficult to tell from the picture, but most likely this is a carpenter ant. Carpenter ants do not eat wood. Carpenter ants chew galleries and make their home in soft wood or wood that is in a state of decay. They take advantage of wood that is being decomposed by fungus or is softened by water damage. I would search for water damaged wood around the home. The ants may only being foraging and not currently established. I am providing a link discussing carpenter ants for you from Pennsylvania cooperative extension https://extension.psu.edu/carpenter-ants