Chevrolet/GMC Express/Savana CNG Compressed Natural Gas Supplement
(GMNA-Localizing-U.S/Canada-9159237) - 2016 - crc - 6/18/15
8 Driving and Operating
During fueling, CNG needs to be
delivered to the vehicle at the
appropriate pressure in relationship
to the ambient temperature. This
can be done automatically by a
temperature compensation system
on the CNG fuel dispenser or
manually by stopping the CNG fill at
a recommended pressure. GM
recommends that customers use
CNG fueling stations that have a
temperature compensation system
whenever possible. Check with the
fuel station. If one is not available,
see the temperature compensation
chart that follows in this section to
choose the appropriate fill pressure
for the ambient temperature. In
addition, fill only to the pressure
level for the lowest ambient
temperature anticipated during
fueling.
Leaving a vehicle connected to a
time fill station can cause the tank
to be filled to a higher pressure than
recommended, especially when
outside temperatures fluctuate.
Disconnect the vehicle from the fill
station as soon as it is full, unless
an auto shutoff feature is used.{Warning
If CNG tanks are filled to a higher
pressure than recommended and
then exposed to a much higher
ambient temperature
environment, expansion of the
gas caused by the temperature
change may cause pressure relief
devices on the vehicle CNG
tank(s) to release gas, as
designed. If an ignition source is
present, this could create a risk of
fire or explosion. If there is any
possibility that the tank has been
over pressurized, take steps to
relieve the excess pressure, such
as by driving or running the
vehicle in an outdoor open area
to remove some fuel.
Make sure that your CNG vehicle is
properly maintained and repaired to
avoid elevated temperatures
surrounding the tank, since elevated
temperatures in the area of the tank
could also raise the CNG pressure
in the tank. Consult materials available from
NGVAmerica - http://www.ngvc.org
and the Clean Vehicle Education
Foundation - http://
www.cleanvehicle.org on CNG
fueling stations for more information.
Ambient Temperature / Maximum
CNG Fill Pressure Compensation
Chart
To avoid the risk of fire or explosion
if an ignition source is present, do
not fill above the pressure level that
corresponds to the lowest ambient
temperature expected during
fueling.
Service Pressure 24 800 kPa
(3,600 psig) at 21 °C (70 °F).
Chevrolet/GMC Express/Savana CNG Compressed Natural Gas Supplement
(GMNA-Localizing-U.S/Canada-9159237) - 2016 - crc - 6/18/15
16 Vehicle Care
The in-tank fuel shutoff valve is
controlled by the ignition switch and
a solenoid on the high pressure
regulator under the vehicle. When
the ignition is in LOCK/OFF or ACC/
ACCESSORY, the solenoid is off
and the valve is closed, shutting off
fuel flow to the engine. When the
ignition is turned to ON/RUN, the
solenoid is on (for three seconds)
and the fuel shutoff valve is open.Manual Shutoff Valve
Locate the manual shutoff valve so
that it can be found quickly if it is
needed.
Chevrolet/GMC Express/Savana CNG Compressed Natural Gas Supplement
(GMNA-Localizing-U.S/Canada-9159237) - 2016 - crc - 6/18/15
18 Vehicle Care
Towing the Vehicle
{Warning
Improperly positioned tow straps,
hooks, or chains can damage the
CNG fuel system and cause a
leak. If leaking gas catches fire, it
could cause injury or death. To
avoid damage, always flatbed on
a car carrier.
See the owner manual for more
information on towing the disabled
vehicle.
Appearance Care
Exterior Care
Finish Damage
{Warning
Heating the vehicle to above 82 °
C (180 °F) may damage the
Compressed Natural Gas (CNG)
tanks and may cause the fuel
pressure relief device to open and
release CNG. If an ignition source
is present, this could create a risk
of fire or explosion.
CNG tank(s) must be drained by
a qualified technician prior to heat
curing a painted body repair.
