VL SERIES STEAMER - ELECTRICAL OPERATION
Pa
e 46 of 88
NOTE: Power the internal contactors on
the low level cut-off and auxiliary low level
cut-off will remain, until the water level
drops below the LLCO probes or the power
switch is turned OFF.
4. Manual reset switch is pressed (momentary).
A. The auxiliary heater contactor is ener
ized
supplyin
power to the heatin
elements
and the heat li
ht (amber) comes on.
1) Water in boiler heats up.
B. Internal relay on manual reset switch is
ener
ized.
1) Normally open contacts close and
lock to provide power to the auxiliary
heater contactor and the heat li
ht
after the reset switch is released.
5. Water reaches LL (low level) probe.
A. Power to terminal 7 on the differential
level control is present but no switchin
occurs.
6. Water reaches HL (hi
h level) probe.
A. Power to terminal 10 on the differential
level control.
1) The internal contactor coil on the
differential level controls is ener
ized.
a. The normally closed contacts on
terminals 3 and 4 open, de-
ener
izin
the boiler fill solenoid
and the boiler stops fillin
.
NOTE: The internal contactor coil has a
lockin
path throu
h contacts on terminals
7 & 8 to the low level probe to keep the
coil ener
ized after the water level drops
below the hi
h level probe.
7. Boiler steam pressure reaches upper limit set
point of 11 PSI. (Approximately 15 min.)
A. Cyclin
pressure switch opens, heater
contactor(s) de-ener
ize and power to the
heatin
elements is removed.
NOTE: Steam should not be seen enterin
a
compartment until the manual steam control
arm is pulled forward and locked.
8. Boiler steam pressure drops below lower limit
set point of 9 PSI and the cyclin
pressure
switch closes.
A. Boiler steam pressure is maintained by the
cyclin
of the pressure switch between the
upper and lower set point limits. The
cyclin
pressure switch continues to
ener
ize and de-ener
ize the heatin
element contactor(s), which in turn, cycles
the heatin
elements on and off. This
sequence continues until one of the
followin
occurs:
1) Boiler pressurizes to 15 PSI, causin
the hi
h limit pressure switch to open.
At that time, the auxiliary heatin
element contactor(s) are de-
ener
ized, shuttin
off power to the
heatin
elements. The pressure
switch will remain open until the
pressure drops below the lower limit
set point of 6 PSI. Boiler water level
drops below the LLCO (low water
level cut-off) probes for the low level
cut-off and the auxiliary low level cut-
off controls, de-ener
izin
the internal
contactor on both controls. This de-
ener
izes the main and auxiliary
heater contactors, shuttin
off power
to the heatin
elements. The heatin
elements will remain off until the
water level rises above the LLCO
probes and the manual re-set switch
is pressed.
COOK CYCLE
1. A Cook cycle should not be started, until the
initial fill and preheat is completed, in order for
the boiler steam pressure to be within
operational limits.
A. Insert product into steamer.
B. Compartment door is closed and screw
handle ti
htened down.
C. Compartment steam control arm is pulled
forward and latches, allowin
steam to
enter compartment.
NOTE: Cool air and condensate exit throu
h
the steam exhaust solenoid valve (N.O.) under
“Full Free Ventin
” until the compartment
temperature reaches 180°F. When the solenoid
valve ener
izes and closes, condensate will
continue to exhaust throu
h a small openin
the valve under “Limited Free Ventin
” until the
solenoid valve de-ener
izes and re-opens, one
minute before the end of a cook cycle.
D. Time is dialed on timer (past 5 minutes).
1) Micro switch SW1 contacts chan
e
state from N.C. to N.O.
2) Micro switch SW2 contacts also
chan
e state from N.C. to N.O.
E. Compartment power switch is turned ON.
1) L1 (HOT) to one side of the thermal
switch.
NOTE: L2 (NEUTRAL) is connected to the
other side of the buzzer, steam exhaust
solenoid valve, trip solenoid, pilot li
ht and
timer motor.
