Section 5: Fuel Conversion/Gas Connections
Installation Guidelines For 60 Hz Air-cooled Generators
19
Natural Gas Pipe Sizing
To determine correct gas pipe size, find the kW rating of
the generator in the left column, and trace to the right.
The number to the right is the maximum length
(measured in meters/feet) allowed for the pipe sizes on
top. Pipe sizes are measured by inside diameter (ID) to
include any fittings, valves (must be full flow), elbows,
tees or angles.
NOTE:
Add 2.5 ft (0.76 m) per any bend, tee or angle in
the pipe to the overall distance. Tables based on
schedule 40 black pipe.
LP Vapor Pipe Sizing
To determine correct LP Vapor pipe size, find the kW
rating of the generator in the left column, and trace to the
right. The number to the right is the maximum length
(measured in meters/feet) allowed for the pipe sizes on
top. The pipe sizes are measured by inside diameter (ID)
to include any fittings, valves (must be full flow), elbows,
tees or angles. Add 2.5 feet (0.76m) per any bend, tee or
angle in the pipe to the overall distance.
NOTE:
Pipe sizes are using a second stage regulator.
NOTE:
The minimum LP tank size is 250 gallons (946 L),
unless unit calculations dictate use of a larger tank.
Vertical tanks, which are measured in pounds (or
kilograms), will not usually meet the minimum tank size
requirement. A 1050 lb (476 kg) vertical tank size
minimum is required.
Installing and Connecting Gas Lines
Natural gas and LP vapor are highly volatile substances.
Strict adherence to all safety procedures, codes,
standards and regulations is essential.
Gas line connections should be made by a certified
plumber familiar with local codes. Always use AGA-
approved gas pipe and a quality pipe sealant or joint
compound.
Table 5-1. Natural Gas Pipe Sizing
For 5-7 inches of water column
(9-13 mm mercury)
For 3.5-5 inches of water column
(7-9 mm mercury)
Allowable Pipe Distances (feet / meters)
Pipe Size
(in / mm)
0.75 / 19
1 / 25
1.25 / 32
1.5 / 38
2 / 51
1 / 25
1.25 / 32
1.5 / 38
8 kW
55 / 16.76
200 / 60.96
820 / 249.94
—
—
20 / 6.1
60 / 18.29
175 / 53.34
11 kW
20 / 6.1
85 / 25.91
370 / 112.78
800 / 243.84
—
—
60 / 18.29
175 / 53.34
16-22 kW
—
20 / 6.1
130 / 39.62
305 / 92.96
945 / 288.04
10 / 3.05
60 / 18.29
125 / 38.1
Table 5-2. LP Vapor Pipe Sizing
For 10-12 inches of water column (19-22 mm mercury)
Allowable Pipe Distances (feet / meters)
Pipe Size (in / mm)
0.75 / 19
1 / 25
1.25 / 32
8 kW
165 / 50.29
570 / 173.74
—
11 kW
70 / 21.33
255 / 77.72
1000 / 304.8
16 kW
25 / 7.62
130 / 39.62
540 / 164.59
20-22 kW
15 / 4.57
115 / 35.05
480 / 146.3
(000192)
DANGER
