"FIREPLACE" INSTALLATION (CONT'D)
FIREPLACE INSTALLATION
Connection of the stovepipe directly into the existing masonry chimney over the fireplace opening is a more desirable method. This instal- lation performs better, yielding more heat and better draft; it is also easy to clean and inspect for creosote. Before beginning this type of in- stallation plan carefully; a high degree of skill is required to insure safety.
An entry port for the stovepipe must be cut through the chimney with minimum damage to the fireclay liner. Some involved measurements may be required to locate the flue liner exactly. Before cutting, take time to mark the size and position of the entry port. Position the entry port so that at least 8 inches of the flue liner remains below the port.
Keep in mind that wood mantels and combustible trim around the fireplace must have adequate clearances from the heater and stovepipe or must be protected in an approved manner. Also, be sure to leave at least an 18 inch clearance between the top of the stovepipe and the com- bustible ceiling or other combustibles. Placing the center of the entry port 2 feet below the ceiling will insure proper clearance for 
Install the stovepipe as far as possible into the thimble, but not past the inside of the flue lining. There should be a small airspace (approximately 1/2 inch) between the stovepipe and thimble, allowing for expansion of the stovepipe. Seal this airspace with
Do not use the Type B installation (not illustrated in this manual), that is, venting up through the fireplace opening, regardless of whether the fireplace opening is closed.
Masonry chimneys have several positive attri- butes: If properly built, they are quite durable, and most homeowners consider them more at- tractive perhaps than an unenclosed factory built chimney. And, if the chimney is located within the confines of the house (that is, not attached to an exterior wall), its mass alone will store heat longer and continue to release the heat long after the fire has died. Masonry chimneys have many disadvantages though. Masonry chimneys constructed on an exterior wall are exposed to cold outdoor temperatures, promoting greater heat loss, higher accumulations of creosote, and reduced draft which leads to poorer heater or furnace performance.
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