LP-Gas Serviceman’s Manual

LP-Gas Regulators
5. Find the line on the chart corresponding to the anticipated inlet
pressure.
6. Draw a vertical line upward from the point of assumed load
(250,000 BTUs per hour) to intersect with the line corresponding
to the lowest inlet pressure.
7. Read horizontally from the intersection of these lines to the
delivery pressure at the left side of the chart. In this example
the delivery pressure will read 10.6” w.c.. Since the delivery
pressure will be 10.6” w.c. at the maximum load condition and
lowest anticipated inlet pressure, the regulator is sized properly
for the demand.
Leak Testing the Installation
According to NFPA 54:
A leak test should be performed on new installation and on
existing systems that are being placed back into service. The test
should include all piping, fittings, regulators, and control valves
in the system.
Over the years, the pressure test and leak test have been
confused with each other. A pressure test is required for
new piping installation and additions to piping installation,
while a leak test is required whenever the gas system is
initially placed into service, or when the gas is turned back
on after being turned off. In this handbook we discuss
the leak test only. For further information regarding the
pressure test, consult NFPA 54, National Fuel Gas Code.
35