Rheem 801C Series, Installation Instructions Manual

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20
Combustion Air
COMBUSTION AND VENTILATION AIR (cont .)
VERTICAL VENT SYSTEMS:
1 . A gas vent shall terminate above the roof surface with a listed
cap or listed roof assembly . Gas vents 12 inches in size or
smaller with listed caps shall be permitted to be terminated in
accordance with Figure 15, provided they are at least 8 feet
from a vertical wall or similar obstruction . All other gas vents
shall terminate not less than 2 feet above the highest point
where they pass through the roof and at least 2 feet higher
than any portion of a building within 10 feet .
2 . A type B-1 gas vent shall terminate at least 5 feet in vertical
height above the highest connected equipment draft hood or
flue collar .
3 . Must rise
1
/
4
” per foot away from the furnace on horizontal
runs and be supported with straps or hangers so it has no
sags or dips . Supports at 4 foot intervals and at all elbows are
recommended .
4 . The vent connector must be mechanically fastened to the
outlet collar of the furnace with at least (2) sheet metal screws
except vent connectors that are B-1 material . These shall be
assembled in accordance with the manufacturer’s instruc-
tions . See Figures 16 and 17 .
5 . Any angle greater than 45 degrees from the vertical is con-
sidered horizontal . The total horizontal distance of a vent plus
the horizontal vent connector serving draft-hood equipped
appliances shall not be greater than 75 percent of the vertical
height of the vent .
Single appliance venting of a fan assisted furnace into a tile-
lined masonry chimney is prohibited . The chimney must be lined
with either Type B vent or with a listed, single wall, metal lining
system . Reference National Fuel Gas Code, ANSI Z223 .1 . See
Figure 18 for typical B-1 vent chase .
NOTE: A chimney adapter is available as an accessory (see
accessory section of this manual). Follow manufacturer’s in-
structions .
SPECIAL VENT SYSTEMS (SVS)
IMPORTANT: It is THE FURNACE MANUFACTURER’s posi-
tion now that new installations of any HTPV pipe used in a cate-
gory
III
vent application, including Selkirk’s Selvent™
II
HTPV
product, should cease immediately.
!
WARNING
DO NOT CONNECT THIS FURNACE TO A CHIMNEY USED
TO VENT A SOLID FUEL APPLIANCE (WOOD OR COAL) .
VENTING WITH A SOLID FUEL APPLIANCE CAN LEAD
TO IMPROPER FUNCTIONING OF THE UNIT, AND DUE
TO SOOTING, THE POSSIBILITY OF FIRE RESULTING IN
PROPERTY DAMAGE, PERSONAL INJURY OR DEATH .
A0991-01
FIGURE 16
ATTACHING TO DRAFT INDUCER COLLAR
LISTED CAP
LISTED GAS VENT
ROOF PITCH = X/12
12
X
“H” - MINIMUM ALLOWABLE HEIGHT
FROM ROOF TO DISCHARGE OPENING
FIGURE 15
TYPICAL VENTING WITH “B-1” VENT
ROOF PITCH
“H” (MIN.) FT.
FLAT TO 6/12 1.0
OVER 6/12 TO 7/12 1.25
OVER 7/12 TO 8/12 1.5
OVER 8/12 TO 9/12 2.0
OVER 9/12 TO 10/12 2.5
OVER 10/12 TO 11/12 3.25
OVER 11/12 TO 12/12 4.0
OVER 12/12 TO 14/12 5.0
OVER 14/12 TO 16/12 6.0
OVER 16/12 TO 18/12 7.0
OVER 18/12 TO 20/12 7.5
OVER 20/12 TO 21/12 8.0
ST-A1220-24
FIGURE 15
TYPICAL VENTING WITH “B-1” VENT
ST-A1220-24