OM-AF30 E V1.02
October 18, 2013
Page 13
ASHFORD 30
INSTALLATION INSTRUCTIONS cont.
CONNECTION TO A METAL PREFABRICATED CHIMNEY
When a metal prefabricated chimney is used, the manufacturer’s installation instructions must be followed
precisely. You must also purchase (from the same manufacturer) and install the ceiling support package or wall
pass through and “T” section package, fi re stops (when needed), insulation shield, roof fl ashing, chimney cap,
etc. Maintain the proper clearance to the structure as recommended by the manufacturer. Th
is clearance is
usually a minimum of 2 inches, although it may vary by manufacturer or for certain components.
Th
ere are basically two methods of metal chimney installation. One method is to install the chimney inside the
residence through the ceiling(s) and the roof. Th
e other method is to install an exterior chimney that runs up
the outside of the residence
(not recommended)
. If it is necessary to run the chimney outside, build an outside
chase around the chimney.
Th
e chimney must be the required height above the roof or other obstruction for safety and for proper draft
operation. Th
e requirement is that the chimney must be at least 3 feet higher than the highest point where it
passes through the roof and at least 2 feet higher than
the highest part of the roof or structure that is within 10
feet of the chimney, measured horizontally (Fig. 1). Th
e
height requirement is necessary in the interest of safety
and does not necessarily assure proper fl ue draft . Use
a minimum total system height of 12 feet, measured
from the stove fl ue collar to the top of the chimney, not
including the chimney cap.
