With the nights getting cooler, our furnaces and stoves which have sat dormant all summer long are beginning to fire up again.  It is a good idea to have your furnace professionally serviced and cleaned prior to the heating season. When was the last time your chimney was cleaned?  Creosote and other flammable substances can build up in chimneys over time and cause fires.  The deposit of these substances occurs more quickly when unclean fuels are burned, such as cardboard, wet wood, and trash.