Raypak HI DALTA HD101 - Manual (Page 28)

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Horizontal Thru-wall Venting
System (Category III) Installation
These installations utilize the heater-mounted blower
to vent the combustion products to the outdoors.
Combustion air is taken from the space and the vent is
installed horizontally through the wall to the outdoors.
Adequate combustion and ventilation air must be sup-
plied in accordance with the NFGC or, in Canada, the
B149 Installation Code.
The total length of the horizontal thru-wall exhaust
vent system should not exceed one hundred (100) feet
in length. If horizontal run exceeds 100 feet, an appro-
priately sized extractor must be used. Each elbow
used is equal to ten (10) feet of straight pipe. This will
allow installation in one of the four following combina-
tions.
· 100’ of straight flue pipe.
· 90' of straight flue pipe and one elbow.
· 80' of straight flue pipe and two elbows.
· 70' of straight pipe and three elbows.
· 60' of straight pipe and four elbows.
The vent cap is not considered in the overall length of
the venting system. The vent must be installed to pre-
vent the flue gas leakage. Care must be taken during
assembly to ensure that all joints are sealed properly
and are airtight.
The horizontal portions of the vent shall also be sup-
ported for the design and weight of the material
employed to maintain clearances and to prevent phys-
ical damage or separation of joints.
The vent must be installed to prevent the potential
accumulation of condensate in the vent pipes. It is rec-
ommended that:
a) The vent be installed with a slight downward slope
of not more than 1/4" per foot of horizontal run to
the vent terminal.
b) The vent be insulated through the length of the
horizontal run.
For appliances installed in extreme cold climate, it is
recommended that:
a) The vent be installed with a slight upward slope of
not more than 1/4" per foot of horizontal run to the
vent terminal. In this case, an approved conden-
sate trap must be installed per applicable codes.
Horizontal Thru-wall Direct Vent
Termination
The flue exhaust direct vent cap MUST be mounted on
the exterior of the building. The direct vent cap cannot
be installed in a well or below grade. The direct vent
cap must be installed at least one (1) foot above
ground level and above normal snow levels.
Multiple direct vent caps MUST NOT be installed with
one combustion air inlet directly above a direct vent
cap. This vertical spacing would allow the flue prod-
ucts from the direct vent cap to be pulled into the
combustion air intake installed above. This type of
installation can cause non warrantable problems with
components and poor operation of the unit due to the
recirculation of flue products. Multiple direct vent caps
should be installed in the same horizontal plane with a
three (3) foot clearance from the side of one vent cap
to the side of the adjacent vent cap(s).
Combustion air supplied from outdoors must be free of
particulate and chemical contaminants. To avoid a
blocked flue condition, keep the vent cap clear of
snow, ice, leaves, debris, etc.
The flue exhaust direct vent cap must be furnished
by the heater manufacturer in accordance with its
listing. Use only the special gas vent pipes listed for
use with Category III gas burning heaters, such as the
stainless steel vent by Heat Fab Inc (800-772-0739),
Protech Systems, Inc. (800-766-3473) or Z-Flex (800-
654-5600). Pipe joints must be positively sealed.
Follow the vent manufacturers installation instructions
carefully.
WARNING: No substitutions of flue pipe or vent
cap material are allowed. Such substitutions would
jeopardize the safety and health of inhabitants.
b) The vent be insulated through the length of the
horizontal run.