Heat & Glo • Paloma • 7031-220 Rev. P • 10/08
17
4. Assemble the desired lengths of pipe and elbows
necessary to reach from the appliance up through
the round support box. Ensure that all pipe and elbow
connections are in their fully twist-locked position.
Assemble as instructed.
5. Cut a hole in the roof centered on the small drill hole
placed in the roof in Step 2. The hole should be of
sufficient size to meet the minimum requirements for
clearance to combustibles, as specified. Continue
to assemble lengths of pipe and elbows necessary
to reach from the ceiling support box/wall thimble up
through the roof line. Galvanized pipe and elbows may
be utilized in the attic, as well as above the roofline.
The galvanized finish is desirable above the roofline,
due to its higher corrosion resistance.
• If an offset is necessary in the attic to avoid
obstructions, it is important to support the vent pipe
every 3 ft. (914 mm) to avoid excessive stress on the
elbows, and possible separation. Wall straps are
available for this purpose, Figure 5.12, page 16.
• Whenever possible, use 45° elbows, instead of 90°
elbows. The 45° elbow offers less restriction to the
flow of flue gases and intake air.
6. Slip the flashing over the pipe section(s) protruding
through the roof. Secure the base of the flashing to
the roof with roofing nails. Ensure the roofing material
overlaps the top edge of the flashing as shown in
Figure 5.14. Verify that the chimney is the required
height above the roof. See roof pitch table, Figure 4.3,
on page 9.
3. To install the round support box/wall thimble cover in
a flat ceiling, cut a 10 in. (254 mm) square hole in the
ceiling, centered on the hole drilled in Step 2. Frame
the hole as shown in Figure 5.13.
FRAMING
1-1/2 in. (38 mm)
LONG WOOD
SCREWS
CEILING JOISTS
ROUND CEILING
SUPPORT BOX/WALL
THIMBLE COVER
Figure 5.13
7. Continue to assemble pipe sections until the height of
the vent (before adding the termination cap) meets the
minimum code requirements as outlined in the current
CAN/CGA-B149 Installation Codes (in Canada), the
National Fuel Gas Code NFPA 54/ANSI Z223.1 (in
USA), or local codes. Note that for steep roof pitches,
the vent height must be increased. See Roof Pitch
Table (
Figure 4.3
, on page 9). In high wind conditions,
nearby trees adjoining rooflines, steep pitched roofs,
and other similar factors can result in poor draft, or
down drafting. In these cases increasing the vent
height or switching to the high wind termination cap
may solve this problem.
8. Slip the storm collar over the pipe, and push it down
to the top of the flashing (
Figure 5.15
). Use non-
hardening sealant above and below the joint between
the storm collar and the pipe.
SHINGLES OVERLAP ON
TOP EDGE OF FLASHING
CAP AND STORM
COLLAR NOT SHOWN
FOR CLARITY
Figure 5.14
OPTIONAL HIGH WIND
TERMINATION CAP
SECURE FLASHING WITH
NON-HARDENING SEALANT AND
ROOFING NAILS
Figure 5.15
