Indications that your chimney needs sweeping
Odors
Burned wood odors(when the chimney is not in use) indicate that the chimney is in need of cleaning.
smoke spilling into the room
If your fires are burning poorly or excess smoke spills into the house, your chimney may need to be cleaned.
a black damper
The damper is positioned directly above the fireplace, making it easy to see and reach. If the damper is caked with creosote, then it's time to sweep your chimney.