Bixby Energy MaxFire Installation & Operating Manual page 19

INSTALLATION IN A CATHEDRAL CEILING
1. Mark a line on the side of the Cathedral Ceiling Support
Box to correspond to the line of the roof pitch. Allow for
the Support Box to protrude below the finished ceiling a
minimum of 2 in (5 cm). See Figure 18.
2. Position the appliance at its proper location on the floor.
Pay close attention to the installation instructions as to
distances from combustibles, etc. The appliance must also
be positioned so the Support Box will not interfere with roof
rafters or other structural framing.
3. Run a plumb line from the center of the flue exit on the
Room Heater to the ceiling. Mark the point on the ceiling
where the plumb line intersects. This represents the center of
the support box. Drill a small hole through the ceiling at this
point, so it can be located from the top of the roof.
4. From the roof, locate and mark the outline of the Support
Box.
5. Remove shingles or other roof covering as necessary to cut
the rectangular hole for the Support Box. Cut the hole 1/8 in
(3 mm) larger than the dimensions of the Support Box. The
rectangular hole should be centered on the small hole which
you drilled through the ceiling to mark the location. Again,
insure that you are not cutting through rafters or framing
members.
6. Run the Support Box through the roof, and place it so that
the bottom of the Support Box protrudes at least 2 in (5 cm)
below the finished ceiling. Align the Support Box vertically
and horizontally with a level. Temporarily tack the Support
Box in place through the inside walls and into the roof
sheathing. See Figure 19.
7. Using tin snips, cut the Support Box from the top corners
down to the roof line, and fold the resulting flap over the
roof sheathing. Before nailing it to the roof, run a bead of
non-hardening sealant around the outside top edges of the
Support Box so as to make a seal between the box and the
roof. Clean out any combustible material or debris from
inside the Support Box. See Figure 20.
2020866 REV A
Figure 18
Figure 19
Figure 20
17