Vermont Casting DVR33 Ventilation Hood User Manual


 
10002823/0 DVR33 15
Vermont Castings, Majestic Products
If a 90º elbow is tted directly onto transition elbow
attached to the appliance ange the maximum horizontal
vent run before the termination or a vertical rise is 36"
(914 mm), Fig. 19.
If a 90º elbow is used in the horizontal vent run (level
height maintained) the maximum horizontal vent length is
reduced by 36" (914 mm), (Fig. 20). This does not apply
if the 90º elbows are used to increase or redirect a vertical
rise (Fig. 18).
Example: According to the chart the maximum horizontal
vent length in a system with a 7.5' vertical rise is 20' (6 m)
and if a 90º elbow is required in the horizontal vent it must
be reduced to 17' (5.2 m).
In Fig. 20 Dimension A plus B must not be greater than
17' (5.2 m).
The maximum number of 45º elbows permitted per side
wall installation is two (2). These elbows can be installed
in either the vertical or horizontal run.
For each 45º elbow installed in the horizontal run, the
length of the horizontal run MUST be reduced by 18"
(45cm). This does not apply if the 45º elbows are
installed on the vertical part of the vent system.
The maximum number of elbow degrees in a system
is 270º (See Fig. 21).
Example: In Figure 21
Elbow 1 = 90º
Elbow 2 = 45º
Elbow 3 = 45º
Elbow 4 = 90º
Total angular variation = 270º
Fig. 19
Fig. 20
Fig. 21