Vermont Casting 820 - Manual (Page 8)

8 8
Vermont Castings Jefferson Direct Vent/Natural Vent Gas Heater
20002191
Vertical Termination - Direct Vent ONLY
A vertical vent system must terminate no less than 8'
(2.44m) and no more than 40’ (12m) above the appli-
ance flue collar. A 2
¹⁄₄ " restrictor plate (supplied) must be
used, where specified, in all vertically terminated vent
systems. (Refer to Figure 8) NOTE: The restrictor plate
supplied with the vertical termination should be
discarded. Install restrictor plate supplied with the
stove directly at stove outlet. A vertically terminated
vent system must also conform to the following criteria:
• No more than two 90˚ elbows may be used.
• Two 45˚ elbows may be substituted for one 90˚ elbow.
No more than six elbows may be used.
• Vent must rise a minimum of 2 feet before offset is used.
• Termination height must conform to roof clearance as
specified in Figure 9.
*The Restictor Plate is used on Direct Vent
installations only.
20
19
18
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Ve
rtical Run (in f
eet)
(Measure from the appliance flue collar to the top of the v
ent pipe
.)
Horizontal Run (in feet)
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
ST132a
Fig. 8 Vertical vent termination window.
ALL VERTICAL
TERMINATIONS
REQUIRE USE
OF THE 2
¹⁄₄
”
RESTRICTOR
PLATE*
Vertical terminations
must be within this area
Unacceptable
Venting Configuration
No Restrictor Plate
Vent Termination Clearances
When planning the installation, consider the location of
the vent terminal and clearances. Some of the most
common clearances to keep in mind are shown in Figure
10.
Important: All vent clearances must be maintained.
Check your vent termination clearances against
Figures 10 and 11.
The vent should be placed so that people cannot be
burned by accidentally touching the vent surfaces when
the stove is operating.
The vent termination should be located where it cannot
be damaged by such things as automobile doors, lawn
mowers or snowblowers and it should be located away
from areas where it could become blocked by snow, etc.
Some considerations are:
• Obstructions or impediments to venting.
• Nearby combustible materials that could come into
contact with combustion exhaust gases.
• Other nearby openings {within 9" (230mm)} through
which exhaust gas could reenter the building.
• All vegetation within 3' (.9m) that may interfere with
the draft.
Other factors that influence where the installation will be
sited include the location of outside walls, where addi-
tional heat may be desired in the home, where the family
members gather most regularly, and perhaps most
importantly, the distance limitations of the venting
system.
IMPORTANT
Direct Vent Only
• The horizontal termination must not be recessed
into the exterior wall or siding.
• Horizontal vent runs must be level toward the vent
termination.
• Clearances around the vent termination must be
maintained.
• For installations using Simpson DuraVent pipe,
parallel installations with minimum wall clearance
have restricted access for connecting the Horizon-
tal Vent Cap straps to the vent pipe. See the
maker’s instructions for recommended installation
procedures.