Glossary

  • Carbon Monoxide: An odorless, colorless, tasteless poisonous gas that is a byproduct of incomplete combustion.
  • Cast Aluminum: A lightweight, rust proof metal made by pouring molten aluminum into pre-shaped molds or casts.
  • Chimney: A structure made of masonry or metal, which surrounds and supports the flues that vent products of combustion from gas, oil, or solid fuel appliances or fireplaces.
  • Chimney Caps: Protective coverings for chimneys usually made of aluminum, galvanized or stainless steel, or copper. Most chimney caps have a mesh screening that serves the dual purpose of spark arrestor and barrier against animals. Chimney caps also prevent rain from entering the flue of the chimney.
  • Chimney Damper Caps: Chimney dampers with caps are mounted to the top of the chimney and are a device which replaces traditional throat dampers. They have caps to protect the chimney from weather.
  • Chimney Liner: The inner portion of the chimney that contains the products of combustion. It can be made of clay tiles or of metal. For flues to be serviceable, they must remain intact and free from perforations, cracks, or damage of any kind that could allow the products of combustion to pass into the living spaces of the home, or the heat from the products of combustion to endanger combustible materials near the flue (such as framing, walls, ceilings, insulation, or floors).
  • Chimney Relining: The repair or replacement of the inner portion of the chimney.
  • Chimney Repair: The process of restoring broken or damaged chimneys to service. This can involve tuckpointing loose brickwork, rebuilding or resealing the crown, or relining the chimney when the chimney liner is cracked, perforated, or broken.
  • Chimney Service: A professional company that sweeps, inspects, repairs, evaluates, and maintains chimneys.
  • Chimney Sweep: A professional who makes his/her living sweeping, inspecting, repairing, and maintaining chimneys.
  • Chimney Sweeping: The process of removing soot, creosote, and debris from a chimney. This should be done on a regular basis in order for the chimney to operate as efficiently and as safely as possible.
  • Damper Cable: The part of a top-sealing damper that runs from the damper down the chimney to the firebox. It has a handle on the firebox end for the purpose of opening and closing the damper.
  • Energy Loss: Heated or cooled air lost from a home to the outside environment through the walls, seals around doors and windows, and/or up the flue of a chimney.
  • Firebox: The location in a fireplace where the fire is built and contained. The firebox is constructed on the inside of a special kind of brick, manufactured for its refractory qualities and its ability to withstand high temperatures.
  • Fireplace: A device of either metal or masonry construction, open on at least one side, and designed to contain a fire. Most commonly used for burning wood for effect rather than heat source.
  • Fireplace Inserts: Wood, coal, pellet, or gas heating appliances that fit inside an existing fireplace.
  • Fireplace Mantel: That part of a hearth setting that protrudes from the surface above the opening of the fireplace and is usually used as a shelf. If made of combustible material, it must be far enough above the fireplace opening to meet NFPA standards.
  • Fireplace Opening: That portion of the fireplace open to the surrounding area.
  • Fireplace Smoke Chamber: The portion of the fireplace located above the firebox and at the base of the chimney flue, where smoke gathers before it is exhausted up and out of the chimney.
  • Flue: Any device used for containing and venting the products of combustion from gas, oil, or solid fuel appliances or fireplaces. Also, the inner part of a chimney that contains the products of combustion from gas, oil, or solid fuel appliances or fireplaces. Flues can be made of clay tiles or of metal.
  • Gas Stoves: Heating or cooking appliances that use natural gas or liquid propane as their fuel.
  • Hearth: The area directly in front of the opening of the fireplace, usually constructed of masonry or other heat resistant material for the purpose of shielding the floor from excessive heat.
  • High-Efficiency Furnace: A heating device that returns to the heating environment more than 90% of the heat it generates. Such a device has, therefore, relatively low flue gas temperatures. The lower flue gas temperatures result in more moisture that condenses on the interior flue walls. This situation significantly increases the opportunity for corrosion within the flue.
  • Low-Efficiency Gas Furnace: A heating device that returns to the heating environment less than 90% of the heat it generates. Such a device has a warm enough flue gas temperature to allow for the vaporization and release to the environment most of the moisture created in the combustion process. This allows for a flue gas environment that is substantially less corrosive than that created by a high-efficiency gas furnace.
  • Throat Dampers: Metal plates installed just above the firebox of a masonry chimney that are used for sealing the flue shut when the fireplace is not in use. Since they seal metal to metal, the seal is quite leaky even when the plates are new. Over time, the plates rust and deteriorate as they are exposed to heat and moisture. When this happens, they lose almost all of their flue sealing capacity.
  • Top-Sealing Damper: A device installed at the top of a chimney for the purpose of sealing the flue shut when the fireplace is not in use. They are often used as replacements for throat dampers that are installed just above the firebox when a masonry chimney is built. Lyemance and Lock-Top top-sealing dampers are as much as 90% more efficient than throat dampers because they provide a silicone rubber gasket seal rather than metal to metal. They are not a replacement for a chimney cap and should be installed under a chimney cap for proper operation in snow and freezing weather.
  • Wood stoves: Enclosed appliances, most commonly constructed of steel or cast-iron, used for burning wood for the purpose of heating an indoor space.