control. They are identical switches, differing only in
their settings.
1.
Remove the boiler control box cover to access
the two pressure switches.
2.
Turn the power ON and let the boiler come up to
pressure.
3.
After the ready light comes ON, turn one of the
cooking compartment timers on to exhaust
steam from the boiler.
4.
Observe boiler pressure gauge readings for
several cycles and compare them with the
pressure settings listed in the table below.
Unit
PRESSURE SETTING (PSI)
CYCLING
HIGH LIMIT
ON
OFF
ON
OFF
Gas
8
10
6
15
Electric
11
13
6
15
NOTE:
Two slotted and square headed adjustment
screws extend through the top of the switch case with
dials and pointers to indicate the approximate setting.
The adjustment screw directly above the dial changes
both the cut-out (off) and the cut-in (on) points. Turning
the screw clockwise increases the pressure.
If the readings differ from the table values, adjust
the pressure settings as described below.
A.
Set the cut-out adjustment screw for the
desired pressure.
B.
Set the cut-in adjustment screw for the
desired pressure.
HIGH LIMIT THERMOSTAT
Disconnect the
electrical power to the machine and
follow lockout / tagout procedures.
NOTE:
On gas boilers, the high limit thermostat is
located behind a small metal cover on the face of the
boiler close to the sight glass on the right side.
NOTE:
On electric boilers, the high limit thermostat is
located behind the contactor box cover. On electric
boilers with two heating elements, the thermostat is
connected to one of the heating element lugs. On
electric boilers with four heating elements, the
thermostat is located between the center pair of
elements at the top of the elements.
Inspect the high limit thermostat and mounting
surfaces as follows:
1.
Remove thermostat (bi-metallic disk type) and
inspect flat surface of thermostat for corrosion or
rust.
•
No rust or corrosion allowed. Replace the
thermostat if its base is rusted.
CAUTION
To ensure proper operation, the
thermostat and associated mounting surfaces must
be cleaned one a year.
NOTE:
A good metal-to-metal contact is essential for
proper functioning of the thermostat.
2.
If required, clean thermostat and thermostat
mounting surfaces.
3.
Reinstall the thermostat.
BOILER ASSEMBLY REMOVAL / REPLACEMENT
Disconnect the
electrical power to the machine and
follow lockout / tagout procedures.
Shut off the gas before servicing the
unit.
All gas joints disturbed during
servicing must be checked for leaks. Check with a
soap and water solution (bubbles). Do not use an open
flame.
•
Check all joints prior to the gas valve
(solenoid) before lighting the unit.
•
Check all joints beyond the gas valve
(solenoid) after lighting the unit.
Newer Steamer Models
1.
Remove the boiler as follows:
A.
Check / ensure that all utilities to the
steamer are off.
B.
Blow down the boiler and allow to cool, if
necessary.
C.
Drain any excess water from the boiler.
D.
Disconnect the steam supply line, power
leads and drain lines from the cooking
compartment top to the boiler base.
NOTE:
The bolts are located behind the small
louvered access panels on the left and right side of the
steamer.
E.
Remove the cooking compartment top by
unscrewing the bolts holding the cooking
compartment top to the boiler base.
VSX BOILER BASE SERIES CONVECTION STEAMERS - SERVICE PROCEDURES
Page 17 of 82
F24627 (0916)
