Vermont Casting DVR33 - Manual (Page 14)

14
Vermont Castings, Majestic Products: DVR33
10004920
Since it is very important that the venting system
maintain its balance between the combustion air
intake and the flue gas exhaust, certain limitations
as to vent configurations apply and must be strictly
adhered to.
The Vent Graph, showing the relationship between
vertical and horizontal side wall venting, will help to
determine the various dimensions allowable.
Minimum clearance between vent pipes and com-
bustible materials is one 1” (25 mm) on top, bottom
and sides unless otherwise noted.
When vent termination exits through foundations less
than 20” (508 mm) below siding outcrop, the vent pipe
must flush up with the siding.
It is best to locate the fireplace a way that minimizes
the number of offsets and horizontal vent length.
The horizontal vent run refers to the total length of vent
pipe from the flue collar of the fireplace (or the top of
the Transition Elbow) to the face of the outer wall.
Horizontal plane means no vertical rise exists on this
portion of the vent assembly.
Vertical Sidewall Application
When installing the appliance as a rear
vent unit, the 90
°
or 45
°
transition elbow
attached directly to the rear of the unit is
NOT INCLUDED in the following criteria
and calculations. Unless this transition
elbow is specifically mentioned, it
should be ignored when calculating
venting layouts.
Fig. 20 Maximum three (3) 90
°
elbows per installation.
Min. 7.5'
(2.3 m)
Max. 20' (6.1 m)
(3) x 90 degree elbows
How To Use the Vent Graph
The Vent Graph should be read in conjunction with the
following vent installation instructions to determine the
relationship between the vertical and horizontal
dimensions of the vent system.
1. Determine the height of the center of the horizontal
vent pipe exiting through the outer wall. Using this
dimension on the Sidewall Vent Graph (Fig. 19), locate
the point intersecting with the slanted graph line.
2. From the point of this intersection, draw a vertical
line to the bottom of the graph.
3. Select the indicated dimension, and position the
fireplace in accordance with same.
Example A:
If the vertical dimension from the floor of the fire-
place is 11’ (3.4 m) the horizontal run to the face of
the outer wall must not exceed 14’ (4.3 m)
Example B:
If the vertical dimension from the floor of the unit is
7’ (2.14 m) the horizontal run to the face of the
outer wall must not exceed 8
¹⁄₂ ’ (2.6 m)
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
eg: A
eg: B
Horizontal Dimension From the Outside Face of
the Wall to the Center of the Fireplace Vent Flange
Vertical Dimension From The Floor Of the unit
To The Centre Of The Horizontal Vent Pipe
Sidewall Vent Graph showing the relationship between vertical
and horizontal dimensions for a Direct Vent flue system.
CFM102
Fig. 19 Sidewall venting graph. (Dimensions in feet.)
• The maximum number of 90˚ elbows per side wall
installation is three (3) (Fig. 20).