Vulcan-Hart VC4EC Service Manual page 28

FULL SIZE ELECTRIC CONVECTION OVENS - SERVICE PROCEDURES AND ADJUSTMENTS
NOTE: If the control was calling for heat when
the calibration mode was entered, heating will
resume after exiting the test mode.
7. Press the Rack 1 key to accept the default "no"
under the "CALY" (calibrate) parameter and
advance the display menu to the "LgOt" (logic
output) test. In this mode, the control and logic
outputs can be turned ON for testing only.
A. Use the arrow keys to change the display
to the appropriate number for testing. Each
test starts automatically, several seconds
after number is selected.
1) #0 - All control outputs are OFF
(fan & heat OFF).
#1 - Heat comes ON
(2CON is energized).
#5 - Convection fan comes ON
(High or Low speed SSR is
energized).
#8 - Electronic beeper (external)
sounds.
B. If the output tests are completed
successfully, proceed to step 4.
C. If the output tests are not completed
successfully, find the source of the
problem. If the problem cannot be repaired,
replace the component and check for
proper operation.
8. Press the Rack 1 key twice to advance past the
"LI" (Logic Inputs test) and reach the "HEY"
(keyboard) test.
A. Press the desired key to display the
corresponding hexadecimal code. This
code is used internally by the control to
identify the key being pressed. See table
below.
KEY CODE
Up Arrow 40
Down Arrow 80
1/2 menu 800
3/4 menu 4000
5/6 menu 2
Set 200
Time 1000
Cook & Hold 8000
*displays 10 momentarily then alternates
between Hey and 0. If pressed again, advances
to the next test.
F25105 (Rev. A, October 2007)
KEY CODE
Start/Stop 4
Temp 20
Rack 1 10*
Rack 2 400
Rack 3 2000
Rack 4 1
Rack 5 8
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B. If the code displayed is not correct for the
key pressed, then the keyboard is
malfunctioning.
1) Turn the power switch OFF.
C. Replace the computer control and check
for proper operation.
9. Press the Rack 1 key to advance the display
menu to the "dISP" (display) test. A test
sequence automatically runs on the display and
control LEDs for a visual verification that all
segments in the LED display and the internal
LEDs are functioning.
10. At the end of the test, the control exits the
calibration mode and returns to the Operation
Mode.
Restore Factory Settings
NOTE: If the computer control does not appear to be
functioning properly, do not restore factory settings
until verifying the control is configured properly as
outlined in SETUP MODE under COMPUTER
CONTROL and performing the COMPUTER
CONTROL OPERATIONAL TEST as outlined in the
above section.
1. Enter the "Calibration Mode" by using the key
sequence stated in step 1 under COMPUTER
CONTROL OPERATIONAL TEST.
A. The computer control outputs are turned
OFF.
B. The display will alternate between "CALY"
and "no".
2. Press the up or down arrow key until the "rESt"
parameter displays.
3. Press the Rack 1 key and "no" displays.
4. Press the up or down arrow key to change the
display to "YES".
5. Press the Rack 1 key to select this data option
and then advance the menu to the "LgOt" (logic
output test).
NOTE: The "g" in LgOt displays as a "9".
6. Press the Rack 1 key twice to advance past the
"LI" (Logic Inputs test) and the "HEY"
(keyboard) test.
7. The "dISP" (display) test sequence
automatically runs.
8. At the end of the test, the control exits the
calibration mode and returns to the Operation
Mode.
9. Enter the "SETUP MODE" as outlined under
COMPUTER CONTROL and perform the
procedure.