Vent Pipe (All Models) And Combustion Air Pipe (Gud Models) Materials - Amana GUX-X Installation Instructions Manual

3. When communicating with the outdoors through
horizontal ducts, each opening shall have a mini-
mum free area of 1 square inch per 2,000 BTU per
hour of total input rating of all equipment in the
enclosure (See Figure 4).
*If the appliance room is located against an outside wall and the air openings communicate
directly with the outdoors, each opening shall have a free area of not less than one square inch
per 4,000 BTU per hour of the total input rating of all appliances in the enclosure.
Figure 4
Equipment Located in Confined Spaces; All
Air from Outdoors. See 5.3.3-b.
4. When ducts are used, they shall be of the same
cross-sectional area as the free area of the open-
ings to which they connect. The minimum dimen-
sion of rectangular air ducts shall not be less than
3 inches.
5.3.4 Specially Engineered Installations:
The requirements of 5.3.3 shall not necessarily govern
when special engineering, approved by the authority
having jurisdiction, provides an adequate supply of air
for combustion, ventilation, and dilution of flue gases.
5.3.5 Louvers and Grilles:
In calculating free area in 5.3.3, consideration shall be
given to the blocking effect of louvers, grilles or screens
protecting openings. Screens used shall not be smaller
than 1/4 inch mesh. If the area through a design of louver
or grille is known, it should be used in calculating the
size of opening required to provide the free area speci-
fied. If the design and free area is not known, it may be
assumed that wood louvers will have 20-25 percent free
area and metal louvers and grilles will have 60-75
percent free area. Louvers and grilles shall be fixed in
the open position or interlocked with the equipment so
that they are opened automatically during equipment
operation.
5.3.6 Special Conditions Created by Mechanical Ex-
hausting or Fireplaces:
Operation of exhaust fans, ventilation systems, clothes
dryers, or fireplaces may create conditions requiring
special attention to avoid unsatisfactory operation of
installed gas utilization equipment.
IV. Vent Pipe (All Models) and
Combustion Air Pipe (GUD Models)
Materials
WARNING
Failure to follow these instructions can
result in bodily injury or death from
asphyxiation. Therefore, carefully read and
follow all instructions given in this section.
In order to achieve high efficiency, the products of combus-
tion from this furnace are cooled to the point where
condensation takes place. Consequently, the venting must
be done in a different manner and with different materials
than with a conventional system. Two- or three-inch PVC
Schedule 40 pipe meeting ASTM D1785, PVC primer
meeting ASTM F656 and PVC solvent cement meeting
ASTM D2564 specifications must be used. Only DWV type
fittings meeting ASTM D2665 and ASTM D3311 can be
used. Carefully follow the manufacturer's instructions in
cutting, cleaning, and solvent cementing of PVC or ABS
pipe.
As an alternate to PVC pipe, primer, solvent cement, and
fittings; ABS materials which are in compliance with the
following specifications may be used: two- or three-inch
ABS Schedule 40 pipe must meet ASTM D1527 and, if
used in Canada, must be CSA listed. Solvent cement for
ABS to ABS joints must meet ASTM D2235 and, if used in
Canada, must be CSA listed. The solvent cement used for
the PVC to ABS transition joint must meet ASTM D3138.
Fittings must be DWV type fittings which meet ASTM
D2661 and ASTM D3311 and, if used in Canada, must be
CSA listed. Carefully follow the manufacturer's instruc-
tions in cutting, cleaning, and solvent cementing PVC or
ABS pipes.
WARNING
Solvent cements are combustible liquids
and should be kept away from all ignition
sources. (i.e. sparks, open flames and
excessive heat). Avoid breathing cement
vapors or contact with skin and eyes.
All 90 degree elbows must be medium (1/4 bend DWV) or
long radius (long sweep 1/4 bend DWV) types conforming
to ASTM D3311. A medium radius (1/4 bend) elbow is 3-
1/16 inch minimum from the plane of one opening to the
centerline of the other opening for 2 inch pipe (4-9/16 inch
for 3 inch pipe).
This furnace must not be connected to any type B, BW, or
L vent or vent connector and must not be vented into any
portion of a factory built or masonry chimney, except when
used as a pathway for PVC pipe as described below
Flexible couplings for joining PVC pipe (sometimes called
"no hub connectors") have been used by some installers to
connect the field supplied portion of the vent system to the
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