Modine Manufacturing HD Series Installation And Service Manual page 11

InsTAllATIon - venTIng
Additional requirements for Common venting:
1. The common vent system and all attached appliances must
be Category I.
2. The vent connector should be routed in the most direct
route from the units to the common vent.
3. Where two or more vent connectors enter a common gas
vent or chimney flue, the smaller connector shall enter at
the highest level consistent with the available head room or
clearance to combustible material.
4. Restrictions within the common vent such as elbows should
be minimized. Each elbow installed within the common
portion of the venting system reduces maximum common
vent capacity by 10% (refer to Tables 11.2 and 11.3 for
capacity)
5. The vent connector capacities included in these tables
allow for the use of two 90 degree elbows (or turns). For
each additional elbow, the vent connector capacity shall be
reduced by 10%. Refer to NFPA54/ IFEC tables for capacity
ratings.
6. The common vent cross sectional area must be equal to or
greater than the largest vent connector cross-sectional area.
7. If all appliances are located on one level of the building, the
vent height shall be measured from the highest draft hood
or vent connector to be installed within the common vent
system (Refer to Figures 11.1 and 11.2).
8. All units must be vented in strict accordance of the common
venting Tables 11.1 through 11.3.
9. All masonry chimneys must comply with all applicable local
and national codes.
10. When combining multiple vent connectors into a manifold
prior to the vertical portion of the common vent, the size of
the common vent manifold and the common vent shall be
determined by applying a 10% reduction (.90 x maximum
vent capacity from Table 11.2 or 11.3) to the common vent
capacity part of the common vent tables. The length of the
common vent manifold (Lm) may not exceed 18 inches per
inch of manifold diameter.
11. Refer to the National Fuel Gas Code for instructions on
multi-level common venting and exterior masonry chimneys
as well as additional installation of the listed applications.
figure 11.1 - Common venting into double Wall B vent
FLASHING
USE LISTED
THIMBLE
TYPE B DOUBLE WALL
COMMON VENT
USE THIMBLE
THROUGH CELLING
TYPE B DOUBLE WALL
VENT CONNECTOR
UPWARD SLOPE VENT
1/4" PER FOOT TOWARDS DRIP LEG.
CATEGORY I APPLIANCE
LISTED TERMINAL
VENT HEIGHT
TEE WITH DRIP
LEG AND
CLEANOUT CAP
RECOMENDED
12" MIN.
REC.
3' MAX
Table 11.1 - maximum vent Connector Horizontal
run (ft) - Type B vent Connector
Connector
dia.
3"
4"
Based on ANSI Z223.1 (NFPA 54)-2009. For reference only.
Table 11.2 - maximum Total Appliance Input Capacities
(mBh) - Type B vent Connector and Type B Common
vent
vent
4 in.
Height
fan+ fan+
(ft)
fan nat
6
92 81
8
101 90
10 110 97
15 125 112
20 136 123
30
152 138
Based on ANSI Z223.1 (NFPA 54)-2009. For reference only.
Table 11.3 - maximum Total Appliance Input
Capacities (mBh) - Type B vent Connector with
Common vent into masonry Chimney
vent
12 in
2
Height
(ft.) fan+ fan+
fan nat
6 NA 74
8 NA 80
10
NA 84
15
NA NA
20
NA NA
30 NA NA
Based on ANSI Z223.1 (NFPA 54)-2009. For reference only.
figure 11.2 - Common venting into masonry Chimney
TYPE B DOUBLE WALL
VENT CONNECTOR
UPWARD SLOPE VENT
1/4" PER FOOT TOWARDS CHIMNEY
CATEGORY I APPLIANCE
6-583.6
model max Horiz. run
30,45,60,75
100, 125
diameter of Common vent
5 in. 6 in.
fan+ fan+ fan+ fan+
fan nat fan nat
140 116 204 161
155 129 224 178
169 141 243 194
195 164 283 228
215 183 314 255
244 210 361 297
Area of Common vent
19 in 28 in
2 2
fan+ fan+
fan+ fan+
fan nat
fan nat
NA 119 NA 178
NA 130 NA 193
NA 138 NA 207
NA 152 NA 233
NA NA NA 250
NA NA NA 270
FLASHING
CHIMNEY
HEIGHT
MASONRY CHIMNEY
(COMMON VENT)
3' MAX
4.5
6
7 in.
fan+ fan+
fan nat
309 248
339 275
367 299
427 352
475 394
547 459
38 in
2
fan+ fan+
fan nat
NA 257
NA 279
NA 299
NA 334
NA 368
NA 404
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