PAGE 14
LPG GAS FUEL
This home generator system has been set up at the
factory for natural gas fuel, unless it has been specifi-
cally ordered for vapor withdrawal liquid propane
gas (LPG). This installation/operation guide will ex-
plain the factory LPG system. Additional information
is available upon request for field conversion from
one fuel to the other.
LPG fuel is typically at farms or remote areas where
there is no natural gas fuel.
LPG must be a vapor withdrawal system (the genera-
tor
will not work on liquid withdrawal systems)
.
Proper LPG is clean and free of moisture or particu-
late matter. It consists of a propane HD5 grade with
minimum 2500 BTU’s per cubic foot energy rating. A
typical blend is 5% propylene and butane plus a
minimum 90% propane.
Required LPG vapor withdrawal fuel pressure is
11-14 inches water column at (6-6½ ounces) 2500
BTU’s per cubic feet.
Figure 4
*BTU VALUES BASED ON 2500 BTU’S PER CUBIC FEET GAS SUP-
PLIER MAY NEED TO KNOW LPG CONSUMPTION AT FULL LOAD,
IN MEASUREMENTS OF CUBIC FT./HOUR OR BTU/HOUR.
Figure 5
CAUTION:
It is critically important to understand,
that as a specific fuel line pipe diameter is extended
in length, its ability to carry the volume of gas, dimin-
ishes in direct proportion.
EXAMPLE 1:
In reading the charts: A model SPH-120,
12 KW generator is to be installed 50 feet from LPG
fuel tank. Figure 4 chart shows this model to require
85 cubic feet per hour, gas volume to be delivered to
generator. Figure 5 chart shows the required 85 cu-
bic feet can be delivered over a 50 foot distance with
¾” diameter fuel pipe.
EXAMPLE 2:
A model SPV-160, 16 KW generator set
is to be installed 70 feet from LPG tank. In reading
the charts, fig. 4 chart show this model to require 135
cu.ft./hr. gas volume to be delivered to generator.
Fig. 5 chart shows the required 135 cu.ft. can be de-
livered over a 50 ft. distance with a 1” diameter fuel
pipe.
INSTALLER’S RESPONSIBILITY: Use Figure 4
chart to learn cubic feet/hour value of generator to
be installed. Use Figure 5 chart to learn minimum
pipe size diameter and maximum distance from
LPG tank to insure sufficient fuel volume from
LPG tank to generator.
CRITICAL POINTS FOR A PROPER LPG
GAS INSTALLATION
Before LPG fuel line plans are made, call your
LPG supplier, give information on the amount of cubic
feet/hour (Figure 4) and BTU’s/hour (Figure 5) that
your generator will use, and ask about local codes
and regulations concerning LPG fuel connected to
generators.
Only LPG vapor withdrawal (not LPG liquid with-
drawal) will work on these generators. Make sure the
LPG tank has the correct fuel.
LPG fuel pressure must be 6 ounce pressure
(11-14 inches water column) delivered to the genera-
tor.
Often new LPG tanks or existing LPG tanks al-
ready located at the installation site, have a pre-
installed, primary regulator set for 250 PSI and in-
tended for home heating and cooking.
This is wrong
for generator fuel.
The LPG fuel tank must have a dedicated primary
LPG fuel regulator mounted at the tank fuel outlet
point, and set for 6 ounce pressure (11-14 inches wa-
ter column). A direct, dedicated fuel line connected
to the 6 ounce fuel tank primary regulator, must be
connected directly to the generator mounted, secon-
dary regulator, also, set at 6 ounce pressure.
LPG FUEL CONSUMPTION AT FULL LOAD
Gen. Model
Gen. KW
Cubic Ft./Hr
BTU/Hr. *
SPS-100
10.0
84
210,000
SPS-120
12.0
88
220,000
SPH-120
12.0
85
212,500
SPV-160
16.0
135
337,500
LPG FUEL LINE MAXIMUM DIAMETERS & LENGTHS
Pipe Length
In Feet
Allowed Distance From LPG Tank
to Gen-Set
0-
10
11-
20
21-
30
31-
40
41-
50
51-
60
61-
70
71-
80
81-
90
Pipe Diamete
r
In Inches
½
110
76
61
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---
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¾
227
157
126
107
95
87
78
70
62
1
428
293
236
201
179
164
151
138
129
1¼
807
523
445
379
338
309
285
255
242
Cubic feet of LPG (vapor withdrawal) that can
safely be carried in it’s matching pipe diameter.
