0 mechanical (cont'd), 1 gas piping and pressures (cont'd) – Reznor ADFH Unit Installation Manual User Manual
Page 10

Form I-ADF, Page 10
From Gas Supply
(horizontal or vertical)
Manual
shutoff
Drip
Leg
*To Gas
Valve
(inside the
cabinet)
*To Gas
Valve
(inside the
cabinet)
Ground
Joint
Union
Drip
Leg
Ground Joint Union
Manual shutoff
FIGURE 6 - Gas Supply
Connection
Gas Supply Piping
Supply Pressure
These direct-fired makeup air systems are designed to operate on a natural gas supply
pressure range of a minimum of 6" w.c. to a maximum of 28" w.c. If the natural gas sup-
ply pressure is above the maximum allowed, it is necessary to install a field-supplied
step-down gas regulator in the supply line. Order and install the appropriate Gas Regu-
lator Kit, Option CZ1 (1") or CZ2 (1-1/2"). Follow the instructions provided with the kit.
Measure the gas pressure between the step-down regulator and the unit.
Maximum Supply Pressure by Manifold
Manifold Option BM75, BM76 - 1/2 psi
Manifold Option BM78, BM79 - 2 psi
6.0 Mechanical
(cont'd)
6.1 Gas Piping and Pressures (cont'd)
Capacity of Piping
Cubic Feet per Hour based on 0.3" w.c. Pressure Drop
Specific Gravity for Natural Gas -- 0.6 (Natural Gas -- 1000 BTU/Cubic Ft)
Specific Gravity for Propane Gas -- 1.6 (Propane Gas -- 2550 BTU/Cubic Ft)
Length
of Pipe
Diameter of Pipe
3/4"
1"
1-1/4"
1-1/2"
2"
2-1/2"
3"
Natural Propane Natural Propane Natural Propane Natural Propane Natural Propane Natural Propane Natural Propane
20'
190
116
350
214
730
445
1100
671
2100
1281
3300
2013
5900
3599
30'
152
93
285
174
590
360
890
543
1650
1007
2700
1647
4700
2867
40'
130
79
245
149
500
305
760
464
1450
885
2300
1403
4100
2501
50'
115
70
215
131
440
268
670
409
1270
775
2000
1220
3600
2196
60'
105
64
195
119
400
244
610
372
1105
674
1850
1129
3250
1983
70'
96
59
180
110
370
226
560
342
1050
641
1700
1037
3000
1830
80'
90
55
170
104
350
214
530
323
990
604
1600
976
2800
1708
90'
84
51
160
98
320
195
490
299
930
567
1500
915
2600
1586
100'
79
48
150
92
305
186
460
281
870
531
1400
854
2500
1525
125'
72
44
130
79
275
168
410
250
780
476
1250
763
2200
1342
150'
64
39
120
73
250
153
380
232
710
433
1130
689
2000
1220
175'
59
36
110
67
225
137
350
214
650
397
1050
641
1850
1129
200'
55
34
100
61
210
128
320
195
610
372
980
598
1700
1037
Note: When sizing supply lines, consider possibilities of future expansion and increased requirements. Refer to National Fuel Gas Code for additional
information on line sizing.
*See gas
connection
location in
FIGURE 1A
or 1B.
Minimum Supply Gas Pressure for Full Fire
Manifold
Option
BM75
BM76
BM78
BM79
with Gas
Control
Option
AG1
AG3
AG 30, 31,
32, 33, 35, 36,
or 37
AG 30, 31, 32, 33, 35,
36, or 37
Manifold
Size
1"
1"
1"
1"
1-1/4"
MBH
Nat
Pro
Nat
Pro
Nat
Pro
Nat
Pro
Nat
Pro
250
4.0
1.4
4.0
N/A
4.1
1.6
4.4
1.6
4.6
1.6
500
5.3
1.9
5.0
N/A
5.8
2.3
6.0
2.3
5.2
1.9
750
7.5
2.7
6.8
N/A
8.5
3.3
8.4
3.3
6.1
2.3
1000
--
--
--
--
12.4
4.7
11.7
4.6
7.4
2.8
1250
--
--
--
--
--
--
--
--
9.1
3.5