Heat & Glo Fireplace XLR-N-CE - Manual (Page 18)

Heat & Glo • XLR-N-CE, XLR-PB-CE • 2198-900 Rev. L • 3/13 18
B. Constructing the Appliance Chase
A chase is a vertical box-like structure built to enclose the
gas appliance and/or its vent system. In cooler climates
the vent should enclosed inside the chase.
NOTICE: Treatment of ceiling firestops and wall shield
firestops and construction of the chase may vary with the
type of building. These instructions are not substitutes
for the requirements of local building codes. Therefore,
you MUST check local building codes to determine the
requirements to these steps.
Chases should be constructed in the manner of all out-
side walls of the home to prevent cold air drafting prob-
lems. The chase should not break the outside building
envelope in any manner.
The factory-supplied non-combustible board must be
used in all installations. It must be directly attached to
structural framing adjacent to the appliance. Screw fas-
teners should be installed in the pilot holes provided in
the outer perimeter of the non-combustible board. See
Figure 13.3.
The factory-supplied board is designed such that its edg-
es will be at the approximate center of the adjacent fram-
ing, assuming it is 3,8 nominal thickness. This will allow
the wallboard joints to occur on the center of the framing
where the panels can be fastened properly. If the framing
thickness is less than 3,8 nominal, such as with formed
steel systems, then it may be necessary to adjust the ad-
jacent framing dimensions so that the non-combustible
board and wallboard joints are centered on the framing.