Duke 155131U, Installation And Operation Manual

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Installation and Operation of 5/9 Electric Convection Oven
MAINTENANCE INSTRUCTIONS
These maintenance instructions are for the use of
qualified service personnel only. Service by other than
qualified personnel may result in damage to the oven
and/or injury to the operator.
Qualified service personnel are those individuals, firms,
companies or corporations which either in person or
through an agent are engaged in and responsible for
repair or servicing of commercial food preparation
equipment, who are experienced in such work, familiar
with all precautions required, and have complied with
all requirements of state and local authorities having
jurisdiction.
If you should require assistance in the selection of
a qualified service agency, please contact duke
manufacturing Co.’s Service department at 800-
735-3853.
A. ADjUSTMENTS
Quite often malfunctions, which are attributed to defects,
may be repaired by adjusting certain parts rather than
replacing them.
B. DOOR SWITCH ADjUSTMENT
you may also wish to adjust the door switch. The door
switch is located behind the combustion compartment
cover, on the right side. The door switch is activated
by a cam, which is mounted to the door’s hinge pin
with a setscrew.
1. Open the door fully.
2. Remove the lower cover by loosening the three
screws located inside the door opening.
3. Position the door so it is nearly closed but not
latched.
4. To adjust the cam loosen the setscrew and rotate
the cam until you hear the switch click.
5. Tighten the setscrew in the cam. Test the door to
make certain the switch will make contact with the
doors closed.
6. Replace the cover.
The door switch is located in
a heated zone. Care should be taken to avoid
burns.
Set
Screw
Cam Door
Switch
Door
C. THERMOSTAT CALIBRATION
Electro-Mechanical Controls Only (“Q” &
“V”). Not applicable to Ovens with Solid
State Controls.
In many convection ovens thermostats have been
the cause of more operating problems than any other
component part. Thermostats, being mechanical devices,
do sometimes fail, in which case only replacing the part
will correct the problem. however, the great majority of
thermostat related problems could be attributed to their
being out of adjustment (calibration). A thermostat that is
out of calibration may cause unsatisfactory cooking results
such as uneven baking, prolonged cooking times, etc. If
you are experiencing uneven cooking, it may be a result
of excessive cooking temperatures. Refer to the cooking
chart provided in Operating Instructions Section C.
To Check Calibration
:
• Turn the oven on by turning the Power Switch to
the ON position.
• Open the doors and place a thermocouple in the
center of the middle oven rack. A reliable mercury-
type thermometer can be substituted if a pyrometer
is not available.
• Turn the thermostat dial to 350°F (177°C). Allow
the oven to preheat 1/2 hour.
• when the indicator light goes out, the thermostat has
been satisfied. Check the pyrometer or thermometer
to determine the internal oven temperature.
• If the reading on the pyrometer (or thermometer) is less
than 10°F different from the setting of the thermostat,