Service manual

-9-
Revision 1/F3503
3.2 EXPLANATION OF CONTROL
SYSTEM
The E26 Turbofan convection ovens feature
multi-function operator controls for which a
correct understanding of their operation is
required before carrying out any service or
fault repair work. The control device functions
are explained as follows:
A power switch on the control panel isolates
power to all the controls of the oven. With the
power switch Off all functions of the oven are
inoperable.
With the power switch On (illuminated) power
is directly supplied to the 60 minute bake
timer, door microswitch, temperature control
circuit, fan motor, and the light switch. The
light switch will turn the oven light on when the
door is closed, but only whilst the light switch
is held in.
The door microswitch on the E26 oven
controls the oven light only. Accordingly the
light will come on when the door is opened but
the circulation fan and fan element will remain
on.
The 60 minute timer is a mechanical timer and
can therefore be operated with the oven’s
power switch On or Off. However, only with
the oven’s power switch On will the switch
contacts of the 60 minute timer turn on the
time-up buzzer and illuminate the time-up
indicator on the control panel. The buzzer
and time-up indicator provide indication that
the time setting has run down to zero and at
this point will remain On continuously until the
60 minute timer has been manually set back
to the Off (vertical) position. The 60 minute
timer does not control any other part of the
oven’s operating system as this timer is
independent of the temperature control and
heating system.
The temperature control of these ovens is with
a capillary type thermostat which can be set to
a required cooking temperature.
The E26 has an element coiled around the
circulation fan in the rear of the oven. Power
to the element is provided directly from the
thermostat. The control panel indicator light
above the thermostat knob cycles on and off
with the thermostat to indicate when the
element is on and the oven is heating. In the
‘Off’ position, the element relies on the
thermostatic control to prevent it switching on.
Accordingly, if the oven temperature drops
below approximately 20°C the thermostat and
element may cycle on at this setting.
The following Troubleshooting Guide should
be used to identify any incorrect oven
operation. On correct identification of the
operating fault the Troubleshooting Guide will
make reference to the corrective action
required, or refer to the Fault Diagnosis
section and/or Service section to assist in
correction of the fault.