Fuel Consumption; Physical Properties; Fuel Type - Briggs & Stratton 40689 Manual De Instalación Y Operación

piping to prevent thermal expansion and contraction
from causing excessive stress on the piping material.
• A union (C) or a flanged connection must be provided
downstream to permit removal.
• A manometer test port (D) should be installed for
vapor fuels. Use the port to install a manometer and
check if the engine receives the correct fuel pressure
for operation. A digital manometer (P/N 19495) or an
analog manometer is available at your service center
for vapor fuels only. When the initial test runs are
completed, the manometer is removed and the port is
plugged.
• For vapor fuels only: Where the formation of hydrates
or ice is known to occur, piping should be protected
against freezing. The termination of hard piping must
include a sediment trap (E) where condensate is not
likely to freeze.
• A minimum of one accessible, approved manual shutoff
valve (F) shall be installed in the fuel supply line within 6
ft (180 cm) of the generator.
• You must install a manual fuel shut-off valve in the
interior of the building.
• Where local conditions include earthquake, tornado,
unstable ground, or flood hazards, special consideration
shall be given to increase strength and flexibility of
piping supports and connections.
• Piping must be of the correct size to maintain the
required supply pressures and volume flow under
varying generator load conditions with all gas appliances
connected to the fuel system turned on and operating.
• Use a pipe sealant or joint compound approved for
use with NG/LP on all threaded fittings to reduce the
possibility of leakage.
NOTICE: Keep thread sealant out of the gas piping to
prevent component part damage.
• Installed piping must be properly purged and
leak tested, in accordance with applicable codes
and standards.
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• (A) Generator Fuel Inlet
• (B) Flexible Fuel Line
• (C) Union Fitting
• (D) Manometer Test Port
• (E) Sediment Trap
• (F) Manual Shut-off Valve

Fuel Consumption

Estimated fuel supply requirements at half and full load for
natural gas and LP vapor fuels are shown in the table that
follows:
LP Vapor (Propane)
12kW
1/2 Load BTU/hr
ft3/hr
gal/hr
Full Load BTU/hr
ft3/hr
gal/hr
Natural Gas
12kW
1/2 Load BTU/hr
ft3/hr
Full Load BTU/hr
ft3/hr

Physical Properties

Normal Atmospheric State
Boiling Point (°F)
Heating Value
BTU per gallon (Net LHV*)
BTU per gallon (gross**)
BTU per cubic feet (gas)
Density***
Weight †
* LHV (Low Heat Value) is the more realistic rating.
** Gross heat value does not consider heat lost in the form of
water during combustion.
*** Density is given in "Cubic Feet of Gas per Gallon of
Liquid."
† Weight is given in "Pounds per Gallon of Liquid."

Fuel Type

Consider the type of fuel that your generator uses, as it
affects the entire installation process. The system was factory
tested and adjusted using natural gas, but it can be converted
to use liquefied petroleum vapor. For correct engine function,
consider factors that affect each of these fuels, such as the
location and the duration of possible utility interruptions.
Follow these guidelines when choosing fuel type:
155,000
62
1.70
209,000
84
2.30
117,000
117
172,000
172
LP Vapor Natural Gas
Gas Gas
-44 -259
83,340 63,310
91,547 n/a
2,500 1,000
36.39 57.75
4.24 2.65
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