Vulcan-Hart VSX Series Service Manual page 38

NOTE: LLCO relays will remain energized and
LLCO LED'S will remain lit until the water level
drops below the LLCO probes or the power switch is
turned off.
4. Water reaches LL (low level) probe.
A. Power to terminal 2 on the water level
control is present but no switching occurs.
5. Water reaches HL (high level) probe.
A. Power to terminal 6 on the water level
control.
1) The inverse latching relay of the is
energized, changing the state of ILR-
1 (N.O.) and ILR-2 (N.C.) contacts.
The inverse latching relay will remain
energized through the alternate
latching path of ILR-1 contacts until
the water level recedes below the low
level probe.
2) With ILR-2 contacts open, HL relay is
de-energized, HL-3 (N.O.) contacts
open and HL LED goes out.
3) Water fill solenoid is de-energized.
(boiler fill time 4-11 min.)
6. Manual re-set switch is pressed.
A. Manual reset switch contacts (N.O.) close
and lock.
B. Heater contactors are energized, suppling
power to the heating elements.
C. Water in boiler heats up.
7. Cooking compartment pressure switch closes
as boiler steam pressure reaches 3 PSI.
(Approximately 14 min.)
A. Cooking compartment ready light (green)
comes on.
NOTE: If a cooking timer is set immediately after
the ready light comes on, a loud clanking sound will
be heard (oil caning) and the ready lights will flash
for several seconds. This condition is caused by the
manifold pressure being on the fringe of the
pressure switch set point. When a cook timer is set,
the compartment steam solenoid valve opens
causing the manifold steam pressure to drop,
slightly below the pressure switch set point. At the
same time, steam pressure is still increasing in the
boiler. This opposing condition causes a pressure
bounce to occur but after the steam pressure passes
approximately 4 psi this condition subsides. Under
normal steam cycling pressures, this condition will
not be seen.
8. Boiler steam pressure reaches upper limit set
point pressure of 13 PSI. (Approximately 15
min.)
VSX SERIES STEAMER - ELECTRICAL OPERATION
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A. Cycling pressure switch opens, heater
contactors de-energize and power to
heating elements is removed.
B. As boiler heats up and builds steam
pressure, some by-pass water/steam is
produced which runs in to the steam drain
box. This causes the cold water condenser
(CWC) solenoid to cycle, cooling the drain
water. This solenoid is powered by the
CWC thermostat.
NOTE: Steam should not be seen entering either
compartment until a cook time is set. This energizes
the steam solenoid valve of the cooking
compartment to allow steam flow.
9. Boiler steam pressure drops below lower limit
set point of 11 PSI and the cycling pressure
switch closes.
A. Boiler steam pressure is maintained by the
cycling of the pressure switch between the
upper and lower set point limits. The
cycling pressure switch continues to
energize and de-energize the heating
element contactor(s), which in turn, cycles
the heating elements on and off. This
sequence continues until one of the
following occurs:
1) Boiler pressurizes to 15 PSI, causing
the High Limit pressure switch to
open. At that time, the auxiliary
heating element contactors are de-
energized, shutting off power to the
heating elements. The pressure
switch will remain open until the
pressure drops below the lower limit
set point of 6 PSI and the manual re-
set switch is pressed.
2) Boiler water level drops below the
LLCO probes for the water level and
the auxiliary low level cut-off controls
which de-energizes the LLCO relays
and changes the contact state of
LLCO-2 (N.O.) back to open. This de-
energizes the main and auxiliary
heating element contactors, shutting
off power to the heating elements.
The heating 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.