66324-YIM-B-1004
10 Unitary Products Group
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FIGURE 5 - EXTERNAL SUPPLY CONNECTION
EXTERNAL SHUT-OFF
TABLE 5: NATURAL GAS PIPE SIZING CHART
1
1.
Maximum capacity of pipe in cubic feet of gas per hour (based
upon a pressure drop of 0.3 inch water column and 0.6 specific
gravity gas).
LENGTH
IN FEET
NOMINAL INCHES IRON PIPE SIZE
1/2” 3/4” 1” 1-1/4”
10 132 278 520 1,050
20 92 190 350 730
30 73 152 285 590
40 63 130 245 500
50 56 115 215 440
60 50 105 195 400
70 46 96 180 370
80 43 90 170 350
90 40 84 160 320
100 38 79 150 305
1 /2 x 1 / 2 G A S C O C K
1 /2 x 1 / 2 U N I O N
A U T O M A T IC
G A S V A L V E
D R IP L E G
1 /2 - 1 4 N P
TABLE 6: PROPANE (LP) GAS PIPE SIZING
CHART
1
1.
Maximum capacity of pipe in thousands of BTU per hour (based
upon a pressure drop of 0.5 inch water column).
LENGTH
IN FEET
NOMINAL INCHES IRON PIPE SIZE
1/2” 3/4” 1” 1-1/4”
10 275 567 1,071 2,205
20 189 393 732 1,496
30 152 315 590 1,212
40 129 267 504 1,039
50 114 237 448 913
60 103 217 409 834
70 96 196 378 771
80 89 185 346 724
90 83 173 322 677
100 78 162 307 630
If flexible stainless steel tubing is allowed by the
authority having jurisdiction, wrought iron or steel
pipe must be installed at the gas valve and extend
a minimum of two (2) inches outside of the unit
casing.
Natural gas may contain some propane. Propane
being a excellent solvent, will quickly dissolve
white lead or most standard commercial com-
pounds. Therefore, a special pipe dope must be
applied when wrought iron or steel pipe is used.
Shellac base compounds such as gaskoloc or sta-
lastic, and compounds such as rectorseal # 5,
Clyde’s or John Crane may be used.
