Have included a snip of the article here, but the whole piece is worth reading, as well as the article link following this one.
I would get a professional in to take care of this problem. Carpenter ants can be very damaging to the structure of your home.
http://www.uky.edu/Ag/Entomology/entfacts/struct/ef603.htm<snip>
When carpenter ants are observed, don't spray them; instead, feed the ants small dabs of diluted honey placed onto the back (nonsticky side) of pieces of masking tape. The best time to do this is late at night since this is when carpenter ants are most active. After the ants have fed on the honey, follow them on their journey back to their nest. Be patient-- eventually the ants will disappear behind a baseboard, cabinet, or into some other concealed location such as the hollow space (void) within a wall, door casing, or porch column.
Treat wall voids and other hidden spaces where ants are entering by carefully drilling a series of small (1/8 inch) holes and puffing boric acid (available at most hardware stores) into the suspected nest areas. The boric acid powder will disperse in the hidden void and contact and kill the ants. If you suspect the nest is in a wall, drill and treat at least 3-6 feet on either side of where ants are entering so as to maximize the chances of contacting the nest. Carpenter ants prefer to travel along wires, pipes and edges. If you suspect the nest location is in a wall, also treat behind pipe collars and behind --not in-- the junction box for electrical switch plates/receptacles. NEVER SPRAY LIQUIDS OR INSERT METAL-TIPPED DEVICES AROUND ELECTRICAL OUTLETS!).
AND
http://www.pestproducts.com/carpenterants.htmIn some areas of the country, carpenter ants (wood ants) cause more damage to structures than termites. They are difficult insects to control and can cause extensive damage to wood members in a fairly short period of time. Carpenter ants do not actually eat wood but excavate galleries within it to use as nesting sites. Foraging activity can occur at any time of day but usually peaks at night. When foraging inside houses, carpenter ants are attracted to sweets, meat, grease and fat.
A carpenter ant colony is usually formed by a queen who begins a nest in a piece of old buried wood or in a partially decayed tree or stump. In mature infestations, there may be as many as ten satellite colonies linked to the parent colony by trails. There is a frequent exchange of workers between these satellite colonies and the main nest. Colonies normally do not produce winged reproductive forms until they are at least three to six years old with emergence of swarmers typically occurring from May through July.