Sterling SF - Manual (Page 16)

16
VENTING (continued)
Figure 6A - Vertical Intake/Vent Installation
* 2 ft. minimum plus maximum snow depth for area.
** If excessive condensation develops, a drip
leg with a condensate drain may be required.
Insulating the pipes may eliminate the problem.
5. Any run of single wall vent pipe passing through an
unheated space must be insulated with an insulation
suitable to 550°F (288°C).
6. The vent system must be installed to prevent
collection of condensate. Pitch horizontal pipes
downward 1/4 in. per foot (21mm/m) toward the vent
cap to facilitate drainage. Vertical vent pipes should
be piped as depicted in Figure 6A.
7. The equivalent length of the vent system must not
be less than 5 ft. (1.5m) and must not exceed
50 ft. (15.2m). Equivalent length equals the total
length of straight pipe plus 10 ft. (3.05m) for each
90° elbow and 4 ft. (1.22m) for each 45° elbow.
8. Each slip joint must be secured with at least three
corrosion resistant screws. Two full turns of 3M #425
Aluminum Foil tape or its equivalent must then be
used to seal each joint. General Electric RTV-108,
Dow-Corning RTV-732 or an equivalent may be used
instead of the tape.
9. For horizontal vent systems longer than 5 ft.
(1.5m), the system must be suppor ted from
overhead building structures at 3 ft. (1m) intervals.
10. The exhaust vent system must remain at a minimum
distance of 6 in. (152mm) from all combustible
materials. Any part of the vent system that passes
through a combustible material must be properly
insulated.
NOTICE: Increasing the clearance distances may
be necessary if there is a possibility of distortion or
discoloration of adjacent materials.
For a VERTICAL vent pipe section that passes through
a floor or roof, an opening 4 in. (102mm) greater in
diameter is required (See Table 1, dimension “M”). The
opening must be insulated and fl ashed in accordance
with applicable installation codes. See Figure 7A.
A HORIZONTAL section of an exhaust vent system that
passes through a combustible wall must be constructed
and insulated as shown in Figure 7B.
2764C