Camus Hydronics DynaMax DMH081 Installation, Operation And Service Manual page 17

Location of a Vertical Air Inlet Opening
1) The total length of piping for inlet air must not
exceed the limits given in Table 8.
2) The air inlet consists of two 90
the point of termination for the vertical air inlet pipe.
o
A 90 elbow and a 90
make this assembly. If a straight piece of pipe is
used between the two elbows, it should not exceed
6" (0.15m) in length. The air inlet opening must be
at least 1 foot below the vent opening. The air
piping must be no further than 2 feet (0.6m) from
the center of the vent pipe. This arrangement
avoids exhaust gases from re-circulating into the
inlet air stream. Refer to Figure 10.
3) Air inlet must terminate at least 3 feet (1.0m) above
the roof or normal snow levels and at least 1 foot
(0.3m) below the vent termination.
4) Locate terminations so they are not likely to be
damaged by foreign objects or exposed to build-up
of debris.
5) Perform regularly scheduled inspections to ensure
that the air inlet terminal is unobstructed.
Figure 12: Vertical Direct Venting Configuration
1) Total length of piping for venting or air must not
exceed limits stated in Table 8.
2) Bottom of the termination shall be located at least 3
feet (1m) above grade or above normal snow levels. In
all cases the appliance shall be
accordance with local codes
3) Termination MUST NOT terminate below a forced air
inlet at any distance
4) Termination cannot terminate below grade. Position
the termination where vapours will not damage walls
or plants or may be otherwise objectionable.
5) Termination shall not be installed closer than 3 feet
(1m) from an inside corner of an L-shaped structure,
window well, stairwell, alcove, courtyard or other
recessed area as wind eddies could affect boiler
performance or cause recirculation.
6) DO NOT terminate closer than 4 feet (1.25m)
horizontally and vertically from any electric meter, gas
meter, regulator, relief valve, or other equipment. In all
cases local codes take precedence
7) Position termination so they are not likely to be
damaged by foreign objects, or exposed to a build-up
of debris.
8) Flue gas condensate can freeze on exterior walls or
on the vent cap. Frozen condensate on the vent cap
can result in a blocked flue condition. Keep the vent
cap/terminal clear of snow, ice, leaves, debris etc.
Some discolouration to exterior building surfaces is to
o
elbows installed at
o
street elbow may be used to
installed
be expected. Adjacent brick or masonry surfaces
should be protected with a rust resistant sheet metal
plate.
9) Perform regularly scheduled inspections to ensure that
the termination is unobstructed.
10) Operate the appliance for one heat cycle to ensure
combustion air and vent pipes are properly connected
to the concentric vent termination connections.
Do not operate appliance with the rain cap removed as this
may result in the recirculation of flue products. Water may
also flow into the combustion air pipe and into the burner
enclosure.
Figure 13: Concentric Vent Vertical Venting
in
Length of Air Inlet Pipe
The maximum total length of the sidewall or vertical roof top
combustion air inlet pipe as installed from the appliance to
the air inlet cap must not exceed 100 equivalent feet (30.5m)
in length. Subtract 3 to 5 feet (1 to 1.5m) of equivalent length
depending on centerline radius for each 90
in the air inlet pipe system. Pressure drop in each 45
will be half as much, 2 to 3 feet (0.6 to 1.0m).
CAUTION
o
elbow installed
o
elbow
12