Connecting The Gas Supply Line To The Furnace Gas Train - Trane Voyager Commercial Installation & Operation Manual

7. Pressure test the supply line before connecting it to the unit to prevent possible gas valve

Connecting the Gas Supply Line to the Furnace Gas Train

Follow the steps below to complete the installation between the supply gas line and the furnace.
Refer to
1. Connect the supply gas piping using a "ground-joint" type union to the furnace gas train and
2. Provide adequate support for the field installed gas piping to avoid stressing the gas train and
3. Adjust the inlet supply gas pressure to the recommended 6" for natural gas or 11" w.c. for LP gas.
Table 16. Sizing Natural Gas Pipe Mains and Branches
Gas Supply
Pipe Run (ft)
10
20
30
40
50
60
70
80
90
100
125
150
175
200
Notes:
1. If more than one unit is served by the same main gas supply, consider the total gas input
2. Obtain the Specific Gravity and BTU/Cu.Ft. from the gas company.
3. The following example demonstrates the considerations necessary when determining the
Example: A 40' pipe run is needed to connect a unit with a 500 MBH furnace to a natural gas
Cu.Ft/Hour = Furnace MBH Input
Gas BTU/Cu.Ft. X Multiplier
Cu.Ft/Hour = 500
*Table is based on a specific gravity of 0.60. Use
RT-SVX34C-EN
damage and the unsafe operating conditions that will result.
Note: Do not rely on gas train shutoff valves to isolate the unit while conducting gas pressure/
leak test. These valves are not designed to withstand pressures in excess of 14" w.c. or
0.5 psig.
Figure 33, p. 52 for the Gas Train configuration.
check for leaks.
controls.
Gas Input (Cubic Feet/Hour)*
1-1/4" 1-1/2"
Pipe Pipe
1050 1600
730 1100
590 890
500 760
440 670
400 610
370 560
350 530
320 490
305 460
275 410
250 380
225 350
210 320
(cubic feet/hr.) and the total length when determining the appropriate gas pipe size.
actual pipe size.
supply having a rating of 1,000 BTU/Cu.Ft. and a specific gravity of 0.60
Table 17, p. 52
Table 16 indicates that a 1-1/4" pipe is required.
local gas supply.
2-1/2" 3"
2" Pipe Pipe Pipe
3050 4800 8500
2100 3300 5900
1650 2700 4700
1450 2300 4100
1270 2000 3600
1150 1850 3250
1050 1700 3000
990 1600 2800
930 1500 2600
870 1400 2500
780 1250 2200
710 1130 2000
650 1050 1850
610 980 1700
Table 17, p. 52 or the specific gravity of the
Installation Piping
4"
Pipe
17500
12000
9700
8300
7400
6800
6200
5800
5400
5100
4500
4100
3800
3500
51