DOMINATOR INSTALLATION AND OPERATION INSTRUCTIONS
Page 10
VERTICAL/CHIMNEY VENTING
The Dominator is listed as a Category I appliance when
vented vertically into a metal chimney system or properly
sized masonry chimney, Figures 1,2, 6 & 7. The chimney
must provide a negative pressure of
.01 to
0.08 in
,
.25
to 2.0 mm
W.C. at the boiler/water heater fl ue collar with
the unit running at full load. A barometric damper must
be installed between the flue collar and the vent
connector. Approved thimbles and fi re-stops must be
used when combustible construction is penetrated.
WARNING : If an appliance using any type of a
mechanical draft system operating under
positive pressure is connected to a chimney
fl ue, never connect any other appliances to this
fl ue. Doing so can result in excessive levels of
carbon monoxide which can cause severe
personal injury or death!
Chimney Inspection & Sizing
A thorough inspection of the masonry chimney must be
performed to ensure that the chimney is clean, properly
constructed, lined and sized. Exterior masonry chimneys
should not be used unless properly lined to prevent
condensation and draft problems. Table 5 lists the
equivalent breeching and fl ue sizes required for the
boiler/water heater. When more than one appliance is
connected to the same chimney fl ue, the fl ue must be
large enough to safely vent the combined output of all
of the appliances.
Table 5 - Equivalent Breeching & Chimney Size
Model Size
Pipe Diameter
in
mm
300
-
400
6
152
600
7
178
750
8
203
900 - 1050
10
254
1350
12
305
1500 - 2100
14
356
Note: These sizes are based on a
20 ft
,
6.1m
chimney height.
Vent Connections
Locate the boiler/water heater as close to the chimney
as possible. Use the shortest, straightest vent connector
possible for the installation. If horizontal runs exceed
5 ft
,
1.5 m
they must be supported at
3 ft
,
0.9 m
intervals with overhead hangers. Use a type B, single
wall stainless or single wall galvanized steel vent pipe
the same diameter as the fl ue collar to connect the
boiler/water heater to a masonry chimney. When using
an approved metal chimney system use the appropriate
vent connector. The vent connector should be sloped up
toward the chimney at a minimum rate of
1/4 in/ft
,
20 mm/m
. On masonry chimneys the connector must
terminate fl ush with the inside of the chimney fl ue,
Figure 2. Fasten each single wall vent connection with
at least 3 corrosion resistant sheet metal screws.
WARNING: Never install a vent pipe having a
diameter different than that of the boiler/water
heater fl ue collar. Failure to comply with this
warning can result in excessive levels of carbon
monoxide which can cause severe personal
injury or death.
Always provide a minimum clearance of
6 in
,
152
mm
between single wall vent pipe and any combustible
materials. Type B1 vent may be used, clearance between
it and any combustible material must be as listed.
WARNING: Failure to maintain minimum
clearances between vent connectors and any
combustible material can result in a fi re causing
extensive property damage, severe personal
injury or death!
DIRECT VENT,
POSITIVE PRESSURE, CATEGORY III
In this confi guration the boiler/water heater blower is
used to push the fl ue products to the outdoors while
drawing combustion air from the outdoors. The
equivalent length of the vent system
must not
exceed
35 ft
,
10.7 m
. The Intake Air Option instructions under
the “COMBUSTION AIR & VENTILATION” section must
be followed! The vent system must be sized per Table 5.
Horizontal Direct Vent Systems - Figures 4 & 5
The vent materials used in horizontal vent systems must
be certifi ed to UL 1738 for installations in the United
States, ULS636 for installations in Canada. The certifi ed
vent terminal from RBI must also be used.
The maximum equivalent length for the horizontal vent
and combustion air pipes is
35 ft,
10.7 m
for each. Each
90° elbow and the vent and intake air terminals are
equal to
10 ft
,
3.1 m
of straight pipe. To maximize the
performance of single wall sheet metal vent systems
locate 90° elbows as far from the boiler as possible and
from one another. For best results, horizontal vent
systems should be as straight as possible.
The vent system must be both gas tight and water tight.
All seams and joints in metal pipes must be joined and
s e a l e d i n a c c o r d a n c e w i t h t h e ve n t s y s t e m
manufacturer’s instructions.
When horizontal vent runs exceed
5 ft
,
1.5 m
they must
be supported at
3 ft
,
0.9 m
intervals with overhead
hangers. The vent system must be pitched down, toward
the vent terminal,
1/4 in/ft
,
21 mm/m
. If any part of a
single wall metal vent system passes through an
unheated space it must be insulated with insulation
rated for
400°F
,
204°C
.
