12
6 720 607 017
GAS PIPING, CONNECTIONS
Before connecting the gas supply, check the rating plate on the right side of the front cover to be sure that the heater is
rated for the same gas to which it will be connected.
In the United States: The installation must conform with local codes or, in the absence of local codes, the National Fuel
Gas Code ANSI Z223.1/NFPA 54.
In Canada: The Installation should conform with CGA B149 INSTALLATION CODES and /or local installation codes.
FOR NATURAL GAS
Maximum Capacity of pipe in Cubic Feet of Gas per Hour
for Gas Pressure of 0.5 Psig or less and a Pressure drop of
0.3 in Water Column.
Follow boxed numbers for piping just one 425 EF
(example: 3/4” B.I. Natural Gas pipe for 30 ft. will handle
152,000 btu’s). For multiple appliances combine the total
btu input load and then refer to applicable chart below.
(Based on a 0.60 Specific Gravity Gas) Btu numbers given
in thousands.
FOR LP GAS
Maximum Capacity of Pipe in Thousands of
BTU per Hour of Undiluted Petroleum Gases
(at 11 inches Water Column Inlet Pressure)
(Based on a Pressure Drop of 0.5 Inch Wa-
ter Column).
Maximum Capacity of Semi-Rigid
Tubing in Thousands of BTU per Hour of
Undiluted Liquified Petroleum Gases (at 11
inches Water Column Inlet Pressure)
(Based on a Pressure Drop of 0.5 Inch Water
Column)
* Source National Fuel Gas Code NFPA 54, ANSI Z223.1 - No
Additional Allowance is necessary for an ordinary number of fittings
GAS LINE SIZING
Nominal
Iron
Le ngth of Black Ir on Pipe , Fe e t
Pipe
Internal
Size,
Diameter
inches inches
10
20
30
40
50
60
70
80
90
100
125
150
175
200
1/4
0.364
32
22
18
15
14
12
11
11
10
9
8
8
7
6
3/8
0.493
72
49
40
34
30
27
25
23
22
21
18
17
15
14
1/2
0.622
132
92
73
63
56
50
46
43
40
38
34
31
28
26
3/4
0.824
278
190
152
130
115
105
96
90
84
79
72
64
59
55
1
1.049
520
350
285
245
215
195
180
170
160
150
130
120
110
100
1 1/4
1.380
1050
730
590
500
440
400
370
350
320
305
275
250
225
210
1 1/2
1.610
1600
1100
890
760
670
610
560
530
490
460
410
380
350
320
2
2.067
3050
2100
1650
1450
1270 1150 1050
990
930
870
780
710
650
610
2 1/2
2.469
4800
3300
2700
2300
2000 1850 1700
1600
1500
1400
1250
1130
1050
980
3
3.068
8500
5900
4700
4100
3600 3250 3000
2800
2600
2500
2200
2000
1850 1700
4
4.026
17,500 12,000 9,700 8,300
7,400 6,80 6,200 5,800 5,400 5,100 4,500
4,100 3,800 3500
Nominal
Iron Pipe
Black Iron Pipe
Size,
Length of Pipe, Feet
Inches
10
20
30
40
50
60
70
80
90
100
125
150
1/2
275 189 152
129 114 103
96
89
83
78
69
63
3/4
567 693 315
267 237 217 196 185 173
162
146
132
1
107 732 590
504 448 409 378 346 322
307
275
252
1 1/4
220 149 121
103 913 834 771 724 677
630
567
511
1 1/2
330 229 185
155 141 127 118 108 102
976
866
787
2
622 433 346
299 264 239 220 204 192 1811 1606 1496
Copper
Outside
Length of Tubing, Feet
Diameter,
Inch
10
20
30
40
50
60
70
80
90
100
3/8
39
26
21
19
_
_
_
_
_
_
1/2
92
62
50
41
37
35
31
29
27
26
5/8
199 131
107
90
79
72
67
62
59
55
3/4
329 216
181
145
131
121 112 104
95
90
7/8
501 346
277
233
198
187 164 155 146 138
