Kohler 14RES

TP-6733 8/11 17Section 1 Installation
1.6 Fuel Requirements
The generator set operates using natural gas or LP
vapor fuel. The generator set is EPA-certified for both
natural gas and LP vapor fuels.
The fuel system installation must comply with the NEC
and local codes.
1.6.1 Fuel Supply
Because of variable climates and geographical
considerations, contact the local fuel supplier for fuel
system planning and installation. Figure 1-8 lists the
recommended fuel ratings and other fuel supply
information for natural gas and LP vapor fuels.
Fuel type
Natural
Gas
LP
Vapor
Fuel supply inlet 1/2 NPT
Fuel supply pressure,
kPa (in. H
2
O),
1.3--2.7
(5--11)
1.7--2.7
(7--11)
Fuel flow rate, maximum, Btu/hr.:
14RES/RESL 193,000 203,000
20RES/RESL 281,000 340,000
Nominal Fuel Rating, Btu/ft.
3
Natural gas 1000
LP vapor 2500
Figure 1-8 Fuel Supply
Verify that the output pressure from the primary gas
utility (or LP tank) pressure regulator is 1.7--2.7 kPa
(7--11 in. water column) and that the utility gas meter
flow rate is sufficient to supply the generator set at rated
load plus all other gas-consuming appliances. See
Figure 1-10 for fuel consumption. Contact the fuel
supplier for flow rate information or a gas meter
upgrade.
The dimension drawing in Section 1.5 shows the
location of the fuel inlet connection. Use flexible
sections to prevent fuel line breakage caused by
vibration. Hold the fuel solenoid valve with a wrench
when tightening the fuel connections. Protect all fuel
lines from machinery or equipment contact, adverse
weather conditions, and environmental damage.
1.6.2 Fuel Pipe Size
Ensure that the fuel pipe size and length meet the
specifications in Figure 1-9. Measure the pipe length
from the primary gas pressure regulator to the pipe
connection on the generator set fuel inlet. Add 2.4 m
(8 ft.) to the measured length for each 90 degree elbow.
Compare the total pipe length with the chart in
Figure 1-9 to find the required pipe size.
Contact local LP provider for LP installation information.
Minimum Gas Pipe Size Recommendation, in. NPT
Pipe
Length,
m (ft.)
14RES/RESL 20RES/RESL
Natural
Gas
(193,000
Btu/hr.)
LP Vapor
(203,000
Btu/hr.)
Natural
Gas
(281,000
Btu/hr.)
LP Vapor
(340,000
Btu/hr.)
8 (25) 3/4 3/4 1 3/4
15 (50) 1 3/4 1 1
30 (100) 1 1 11/4 1
46 (150) 11/4 1 11/4 11/4
61 (200) 11/4 1 11/4 11/4
Figure 1-9 Fuel Pipe Size Recommendations
Fuel Type % Load
Fuel Consumption, m
3
/hr. (cfh)
14RES/RESL 20RES/RESL
60 Hz 50 Hz 60 Hz 50 Hz
Natural Gas
100%
5.4 (193) 4.9 (175) 8.0 (281) 6.4 (225)
75%
4.7 (163) 4.2 (148) 6.9 (243) 5.4 (189)
50%
3.5 (124) 3.1 (108) 4.6 (161) 3.9 (139)
25%
2.6 (93) 2.4 (84) 3.6 (127) 2.9 (103)
LP Vapor
100%
2.3 (81) 2.1 (74) 3.9 (136) 2.9 (102)
75%
2.1 (75) 1.9 (68) 3.1 (109) 2.4 (85)
50%
1.8 (60) 1.5 (53) 2.3 (82) 1.8 (63)
25%
1.2 (45) 1.1 (40) 1.7 (59) 1.3 (47)
LP vapor conversion factors:
8.58 ft.
3
=1lb.
0.535 m
3
=1kg
36.39 ft.
3
= 1 gal.
Nominal fuel rating:
Natural gas: 37 MJ/m
3
(1000 Btu/ft.
3
)
LP vapor: 93 MJ/m
3
(2500 Btu/ft.
3
)
Figure 1-10 Fuel Consumption