14
When the initial test runs are completed, the manometer
is removed and the port is plugged. A typical final fuel
connection assembly is shown here, where (
a
) is the fuel
supply and (
B
) goes to the home generator.
It is recommended that the fuel connection incorporate the
following components:
• A minimum 10 ft. (3 m) section of gas pipe between
the primary fuel regulator and the generator fuel inlet
connection (acts as accumulator for high block loads).
• 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 to ensure that the engine receives the
correct fuel pressure to operate efficiently throughout its
operating range.
fuel Pipe sizing
There are numerous on-line or otherwise-published
references for fuel pipe sizing. For example, NFPA 54 -
National Fuel Gas Code, 2006 (Item #: 320-6031-06) is a
common resource. The installer should consider the specific
gravity of gas and compensate for a nominal amount of
restriction from bends, fittings, etc. If an unusual number of
fittings, bends, or other restrictions are used, refer to federal
and local codes for guidance.
A
B
