Computer Control - Vulcan-Hart VC4EC Service Manual

FULL SIZE ELECTRIC CONVECTION OVENS - SERVICE PROCEDURES AND ADJUSTMENTS
C. Tighten right turnbuckle.
D. Tighten locknuts on both turnbuckles.
5. If the right door leads the left door by more than
3/8 inch:
A. Loosen locknuts on both turnbuckles.
B. Loosen right turnbuckle.
C. Tighten left turnbuckle.
D. Tighten locknuts on both turnbuckles.
6. Check door for proper operation.
NOTE: The locknuts must be tight during testing or
the adjustment will not hold.
A. If doors do not close properly, repeat step
4, 5 and 6.
B. If doors operate properly, continue to step
7.
7. Install the lower front cover.

COMPUTER CONTROL

Operation
Refer to the Instructions Manual for specific
operating instructions.
Setup Mode
NOTE: Use the setup mode to verify that the control
is configured to the factory settings which result in
the proper operation of the oven. If the CAL1
parameter is other than zero, determine if it is still
needed before resetting to zero. See COMPUTER
CONTROL TEMPERATURE CALIBRATION.
Changing the C_F, InP1, rL1 & rH1
parameters will default all menus to the factory
settings.
1. Use this key sequence to access the setup
mode.
Up arrow; Rack 1; Temperature; Temperature;
Down arrow; Rack 1
2. Once in the setup mode the display will
alternate between the parameter and
programmed data.
• To change data to the factory setting, use
the arrow keys.
• To select the next parameter, press the
Rack 1 key.
• After the last Parameter and Data is
viewed, press the Rack 1 key a final time
to exit the setup mode and return to
operations mode. The current set point
temperature will be displayed.
• After 1 minute of no key activations, the
control will return to operation mode.
3. Listed are the parameters and data you should
find.
MENU
Celsius_Fahrenheit
Guard Band
Temperature
Compensation
Input Type 1
Range Low 1
Range High 1
Hysteresis
Calibration Offset
Exit Setup Mode and
return to Operation
Mode.
Probe Test
If the oven is not heating or displaying the proper
temperature, the temperature probe may be
malfunctioning. Determine if the probe is good or
causing the operational problem. Temporarily,
disconnect the existing probe lead wires from the
computer control and connect the lead wires from a
known good "J" type thermocouple. Secure the
sensing end of the thermocouple near the probe.
Turn the power switch ON and set the dial to 350°F.
If the oven reaches the set temperature and cycles
with the temporary thermocouple, then the existing
probe is malfunctioning. Replace temperature probe
with the correct part and check for proper operation.
Solid State Relay Test
The solid state relays "SSR1 or SSR2" supply power
to the blower motor "high" or "low" fan speed
terminals when the SSR is energized by the output
voltage from the computer.
To test solid state relay "SSR1" (high fan speed), the
computer control should be in the "Normal Cooking
Mode". To test solid state relay "SSR2" (low fan
speed), the computer control should be in the "Cook
& Hold Mode".
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ALTERNATING ON
DISPLAY
PARAMETER DATA
C_F
gb 4000
tcnP OFF
InP1
rL1
rH1
HYS1
CAL1
set point temperature is
displayed or if call for
heat, dashes (----)
displayed.
F25105 (Rev. A, October 2007)
F
J
75
500
3
0