Dunkirk XEB-2 Installation Instructions Manual page 13

1. These boilers may be vented horizontally as
shown in Fig. 9. The vent pipe is pitchedl[!_!_fJm
from the boiler to the vent termination. Do not
connect other appliances to this vent.
2. Vent Pipe Material:
a) UL Listed Z-Flex Z-Vent stainless steel vent
pipe from boiler to vent termination,
-or-
b)
UL Listed Heat-FabSaf-T-Vent stainless steel
vent pipe from boiler to vent termination,
-or-
c) UL Listed Flex-L StaR-34 stainless steel vent
pipe from boiler to vent termination,
-or-
d) UL Listed ProTech FasNSeal stainless steel
vent pipe from boiler to vent termination.
3. Clearance to Combustible Materials:
For stainless steel vent pipe maintain 6" minimum
air space clearance to combustible materials.
4. Vent Pipe Size:
a) 2, 3, 4 and 5 section boilers use 3" vent pipe
connected directly to the outlet of the induced
draft blower.
b) 6 and 7 section boilers use 4" vent pipe,
starting with a 3" to 4" stainless steel vent
pipe transition that is connected directly to
the outlet of the induced draft blower. Do not
use 3" vent pipe on 6 or 7 section boilers.
5. Vent Pipe Length:
a) For stainless steel vent pipe, the maximum
horizontal vent length is 30 feet plus one 90 °
elbow plus termination fitting.
b) Minimum horizontal vent length for all vent
materials is 2 feet plus one 90 ° elbow plus
termination fitting.
c) For additional elbows reduce the maximum
vent length as shown:
3"- 90° ebow- reduce vent len91h3 feet per each 3"
elbow,
4" - 90 ° elbow - reduce vent length 6 feet per
each 4" elbow.
Example: 6 section boiler requires 3 elbows
plus the termination fitting. This means 2
additional 4" elbows will be used, at 6 feet
per elbow. This is equivalent to 12 feet of
pipe (2 x 6 =12), therefore maximum vent
length is now 18 feet (30 -12 =18). 12
6. Vent Termination Fitting:
For all vent pipe materials, you may use either:
a) a 90 ° elbow pointing down, fitted with a
minimum 1/4" mesh screen to keep out
rodents and birds. The elbow shall be of the
same material and size as vent pipe. The
elbow exit should be at least 6" away from
exterior wall as shown in Figure 9.
-or-
b)
Tjernlund VH-1 Series side wall vent hood.
For 2, 3, 4, 5 section boilers use VH-1-3", For
6, 7 section boilers use VH-1-4".
7. Vent Pipe Termination Location:
a) When venting through combustible walls,
combustible clearances must be considered.
The VH-1 Side wall vent hood provides both
the outside vent termination and a double
wall pipe for passing through a combustible
wall up to 8" thick (VH-1-4") or 9" thick (VH-
1-3"). The hole in the wall must be 6%" square
for 3" vent pipe and 7 1/2" square for 4" vent
pipe, in order to insert the VH-1 side wall
vent hood. The VH-1 may also be used in
noncombustible walls.
b) If the 90' elbow is the termination fitting of
choice, then the single wall pipe will be passing
through the side wall. For combustible walls,
a UL listed thimble shall be used where the
single wall pipe passes through the wall. For
combustible walls using Z-Vent, Sat-T-Vent,
or StaR-34 vent pipe, use the following:
3" vent pipe - use Simpson's Duravent
#905295 3" thimble or equivalent
4" vent pipe - use Simpson's Duravent
#915295 4" thimble or equivalent Maximum
wall thickness with this thimble is 7 inches.
For combustible walls using ProTech
FasNSeal where the single wall vent pipe must
pass through the side wall, a UL Listed
FasNSeal wall thimble shall be used as
follows:
3" FasNSeal vent pipe - use 3" FasNSeal Wall
Thimble #FSWT03 4" FasNSeal vent pipe - use
4" FasNSeal Wall Thimble #FSWT04
The thimble is adjustable for different wall
thickness, with a maximum wall thickness of
7 inches. Seal the thimble along the outside
edge of the plate with caulk or silicone and
fasten to the wall with screws or nails.