7
FIAT PUNTO NATURAL POWER
3) Excess flow,it intervenes if the piping
is broken limiting the flow of methane to
values that are not dangerous.
The flow restricter valve is located to al-
low it to operate even if the solenoid valve
casing is broken due to an impact.
4) Manual tap,it is located upstream of
the solenoid valve.
SOLENOID VALVES/
SAFETY DEVICES
The solenoid valves Fig. 5and Fig. 6are
bolted directly onto the methane canis-
ters with the main function on interrupt-
ing the flow of methane to the supply cir-
cuit.
The solenoid valves are open when:
❒the switching button is in the methane
position;
❒the pressure in the canister is sufficient
for operation;
❒the engine is running;
❒the inertia switch has not been trig-
gered.
The solenoid valve assembly is equipped
with the following safety devices:
1) Fuse pad,in the case of overheating
(temperature above 110 °C), it totally
eliminates the danger of excess pressure
making the methane in the canister flow
out as quickly as possible in a controlled
manner.
2) Mechanical excess pressure device
(Burt Disk),in the case of excess pres-
sure (above 330 bar), it ensures that the
methane escapes as quickly as possible in
a controlled manner.It separates the canister from the methane
system to allow maintenance operations.
The taps are accessible from outside the
car and are located, in the case of the
lengthwise centre canister, at the rear of
the canister and, in the case of the trans-
verse rear canister, towards the right
wheel side.
To close the taps D-Fig. 7: turn the knob
in the direction (1) shown by the arrow
(clockwise
OFF)
To open the taps D-Fig. 7: turn the knob
in the direction (2) shown by the arrow
(anti-clockwise
ON)
5) Single-acting valve,this prevents the
methane from flowing back to the filler.
fig. 5F0M0454m
fig. 6F0M0455m
fig. 7
D
1
2
F0M0456m
603_97_333 Punto FL Nat P GB 1ed 6-08-2009 10:50 Pagina 7