28
Installation & Operation Manual
TABLE - 3C
GAS PIPING SIZE CHART
Nominal
Iron Pipe
Size
Inches
Length of Pipe in Straight Feet
Maximum
Capacity of Pipe
in Thousands of
Btu/hr per hour
for gas pressures
of 14 Inches
Water Column
(0.5 PSIG) or less
and a pressure
drop of 0.5 Inch
Water Column
(Based on NAT
GAS, 1025 Btu/hr
per Cubic Foot
of Gas and 0.60
Specific Gravity)
10
20
30
40
50
60
70
80
90
100
125
150
175
200
3/4
369
256
205
174
155
141
128
121
113
106
95
86
79
74
1
697
477
384
328
292
267
246
256
210
200
179
164
149
138
1 1/4
1,400
974
789
677
595
543
502
472
441
410
369
333
308
287
1 1/2
2,150
1,500
1,210
1,020
923
830
769
707
666
636
564
513
472
441
2
4,100
2,820
2,260
1,950
1,720
1,560 1,440 1,330
1,250
1,180
1,100
974
871
820
2 1/2
6,460
4,460
3,610
3,100
2,720
2,460 2,310 2,100
2,000
1,900
1,700 1,540 1,400
1,300
3
11,200
7,900
6,400
5,400
4,870
4,410 4,000 3,800
3,540
3,300
3,000 2,720 2,500
2,340
4
23,500 16,100 13,100 11,100 10,000 9,000 8,300 7,690
7,380
6,870
6,150 5,640 5,130
4,720
Gas piping
Install piping to control
1. The gas line should be a separate line direct from the meter
unless the existing gas line is of sufficient capacity. Verify
pipe size with your gas supplier.
2. Use new, properly threaded black iron pipe free from chips.
If tubing is used, make sure the ends are square, deburred
and clean. All tubing bends must be smooth and without
deformation. Avoid flexible gas connections. Internal
diameter of flexible gas lines may not provide appliance
with proper volume of gas.
3. Run pipe or tubing to the unit’s gas inlet. If tubing is used,
obtain a tube to pipe coupling in order to connect the
tubing to the unit’s gas inlet.
4. Install a sediment trap in the supply line to the unit’s gas
inlet (see FIG. 3-1).
5. Remove seal over gas inlet to the appliance.
6. Apply a moderate amount of good quality pipe compound
(DO NOT use Teflon tape) to pipe only, leaving two end
threads
bare.
7. Connect gas pipe to inlet of appliance. Use a wrench to
support the gas manifold on the appliance.
8. For LP gas, consult your LP gas supplier for expert
installation.
Figure 3-1_Gas Line Connection with Sediment Trap
(Drip Leg) and Manual Main Gas Shutoff Valve
All gas connections must be made with pipe joint compound
resistant to the action of liquefied petroleum and natural
gas. All piping must comply with local codes and ordinances.
Tubing installations must comply with approved standards and
practices.
3
Gas connections
