To see a chimney in your dream represents warmth, tradition, and family values. Alternatively, a chimney symbolises the phallus. So if the chimney is smoking, then it represents sexual release. If it is not smoking, then it signifies sexual tension or your need for sexual release. If the chimney collapses, then it implies impotence.
To dream that you are sweeping the chimney indicates your need to vent off your frustrations and get things out in the open. You need to release all that negativity and/or guilt that you are holding in.