Cooking Control Calibration; Electronic Ignition System - Vulcan-Hart 1GR45A Service Manual

GRA SERIES GAS FRYERS - SERVICE PROCEDURES AND ADJUSTMENTS
COOKING CONTROL
CALIBRATION
NOTE: Verify condition of temperature probe as
outlined under TEMPERATURE PROBE TEST
before proceeding.
1. Check the level of shortening in fry tank. The
level must be between the MIN & MAX fill lines
before proceeding.
2. Allow shortening to cool below 300EF.
3. Place a thermocouple in the geometric center of
the fry tank one inch below the shortening
surface.
4. Set the cooking control to 350EF and turn the
fryer on.
5. Monitor the burners as they cycle on and off.
NOTE: Agitate the shortening, to eliminate any cold
zones.
A. Allow burners to cycle three times to
stabilize shortening temperature.
B. Record meter reading from thermocouple
when the burners cycle off and on for at
least two complete heating cycles.
Calculate the average temperature by adding
6.
the temperature reading when the burners go
out to the temperature reading when the
burners come on & divide this answer by 2.
[ Temp. (Burners off) + Temp. (Burners on) ] ÷ 2 = Average
Temp.
Example: 360° + 340° ÷ 2 = 350°F.
The average temperature should be
350EF (± 5EF).
A. If the average temperature reading is
within tolerance, cooking control is properly
calibrated.
B. If the average temperature reading is out of
tolerance, loosen set screw to remove
temperature knob and adjust calibration
potentiometer.
1)
7. Repeat the average temperature calculation for
up to three attempts. Allow the cooking control
to cycle at least two times between adjustments
before performing the calculation.
8. If calibration is unsuccessful, the cooking
control may be malfunctioning and cannot be
adjusted properly. Install a replacement cooking
control and check calibration.

ELECTRONIC IGNITION SYSTEM

Operation
When the main power switch is turned on the ignition
control module is energized with 24 volts between
terminals 5 and 6.
An output of 24 volts is sent from terminals 2 and 3
to the pilot coil on the combination valve, allowing
gas flow to the pilot; and spark voltage is sent from
SPARK terminal to begin sparking at the
ignitor/flame sense electrode. The sparking will
continue until an adequate pilot flame is sensed or
for a maximum of 90 seconds.
If pilot is not established within the 90 second ignition
trial time, the ignition module locks out power to the
gas valve. Controls will be disabled.
The system remains locked out until the power
switch is cycled to reset the system and re-start the
ignition trial cycle.
Once the pilot flame is confirmed, a 24 volt output
from terminal 1 will provide the ignition status input
signal to the cooking control. When the cooking
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Adjust calibration potentiometer
clockwise to increase temperature,
and counterclockwise to decrease
temperature.
a. If over 25E of adjustment is
necessary, replace cooking
control.
F25377 (March 2010)