An open wood fireplace consists of a hearth where wood is burned for heat and a chimney flue for expelling the smoke. Because heat can be lost with the smoke, a fireplace insert is often installed to increase heat retention. A freestanding wood stove, pellet stove, and gas stove also decorates and warms a home and requires some of the same maintenance and repair as a fireplace. (The terms "stove" and "fireplace" typically are used interchangeably.)
All fireplaces have the same two requirements: regulated air to feed the fire and a means of expelling smoke and fumes. A shuttered damper in the chimney provides an exit for smoke as well as creates an updraft that draws fresh air to the fire. Many new fireplace designs also use outside air intake vents under the fireplace so as not to draw warm air from the room. Gas fireplaces often have an inlet/outlet vent that expels fumes through a duct in an outside wall while drawing in fresh air.
Pellet stoves burn pellets made from sawdust and mill shavings; the pellets are loaded into a hopper at the top or front of the stove and delivered to the combustion chamber at a controlled rate by a motorized auger. Combustion air, blown into the chamber, develops superheated air. Room air is drawn across the heat exchanger by a fan, heated, and then returned to the room. Residual combustion gasses are vented outside, normally through a 3-inch flue that exits out the unit's back or top.
Sweep a chimney:
- Remove all loose items from the fire surround and the hearth.
- Cover the fireplace opening with a heavy fabric cover and seal it with duct tape. Also cover nearby flooring and furniture with a dropcloth.
- From atop the roof, push a chimney brush from the chimney top down toward the fireplace below, moving the brush up and down to loosen debris.
- Continue pushing the brush down the chimney by adding extension canes and moving the brush to loosen debris.
- When the brush reaches the bottom of the chimney, withdraw the brush.
- Allow the dust to settle for at least one hour before removing the cover over the fireplace opening.
- Use a shop vacuum cleaner to remove debris from the fireplace floor and the smoke shelf.
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