Rheem RESIDENTIAL GENERATOR SYSTEM GEN12S - Manual (Page 11)

• Install the flexible, gaseous hose (supplied) between
the generator system Fuel Inlet port and rigid piping to
prevent thermal expansion or contraction from causing
excessive stress on the piping material.
NOTE: 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 an approved pipe sealant or joint compound on all
threaded fittings to reduce the possibility of leakage.
• Installed piping must be properly purged and leak
tested, in accordance with applicable codes and
standards.
Consider the following factors when planning to install the
fuel supply system:
The generator system engine is fitted with a fuel mixer
system that meets the specifications of the California Air
Resources Board for “tamper-proof” dual fuel systems. The
unit will run on natural gas or liquefied propane (LP) vapor.
• A minimum of one accessible, approved manual shutoff
valve must be installed in the fuel supply line within 6 ft
(1.8 m) of the generator system. A union or flanged
connection must be provided downstream from this
valve to permit removal of controls.
• Natural gas fuel supply pressure at the generator's fuel
inlet port should be between 5 to 7 inches of water (in.
W.C.) with the generator off and at full load with all gas
appliances turned on and operating. LP fuel supply
pressure should be 11 to 14 inches of water (in. W.C.)
with the generator off and at full load with all gas
appliances turned on and operating.
The generator system has been factory set to run on
natural gas. If you need to change from natural gas to LP
gas, the unit will need to be reconfigured, as described later
in this manual.
It is recommended that the fuel connection incorporate the
following components:
• A manual fuel shut-off valve located in the interior of
the building.
• A manual fuel shut-off valve located outside the
building, just before the generator unit.
• Where the formation of hydrates or ice is known to
occur, piping should be protected against freezing. The
termination of hard piping should include a sediment
trap where condensate is not likely to freeze.
• A manometer port should be provided.
The manometer port permits temporary installation of a
manometer (Figure 5), to ensure that the engine receives the
correct fuel pressure to operate efficiently throughout its
operating range.
When the initial test runs are completed, the manometer is
removed and the port is plugged. A typical final fuel
connection assembly is shown in Figure 6.
9
Figure 6 — Completed Fuel Connections
Figure 5 — Temporary Manometer Installed
From fuel
supply line
To generator
• Before placing the generator system into service, the fuel system
lines must be properly purged and leak tested.
• NO leakage is permitted.
WARNING
Propane and Natural Gas are extremely flammable
and explosive.
Fire or explosion can cause severe burns or
death.
• The entire flexible gaseous pipe must be visible for periodic
inspection and must not be concealed within, contact, or run
through any wall, floor, or partition.
CAUTION
The supplied flexible gaseous pipe is not to be installed
underground or in contact with the ground.