Moffat E25-2 Service Manual
E25 CONVECTION OVEN
SERVICE
MANUAL
Revision 4/F3501
July, 2003
Manual P/N M0ME25
WARNING: ALL INSTALLATION AND SERVICE REPAIR WORK MUST BE CARRIED
OUT BY QUALIFIED PERSONS ONLY.
Revision 4/F3501
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CONTENTS
This manual is designed to take a more in depth look at the E25 convection oven for the purpose of
making the unit more understandable to service people.
There are settings explained in this manual that should never require to be adjusted, but for
completeness and those special cases where these settings are required to change, this manual
gives a full explanation as to how, and what effects will result.
SECTION PAGE NO.
1. SPECIFICATIONS ........................................................................................................ 5
2. INSTALLATION ............................................................................................................ 7
3. OPERATION ................................................................................................................. 8
3.1 Description of Controls—E25
3.2 Description of Controls—E25B
3.3 Explanation of Control System
4. MAINTENANCE ............................................................................................................ 12
4.1 Cleaning
4.2 Routine Procedures
5. TROUBLE SHOOTING GUIDE .................................................................................... 13
6. SERVICE PROCEDURES............................................................................................. 16
6.1 Fault Diagnosis
6.2 Access
6.3 Replacement
6.4 Adjustment / Calibration
7. ELECTRICAL SCHEMATICS ....................................................................................... 30
7.1 E25
7.2 E25B
8. ELECTRICAL WIRING DIAGRAMS............................................................................. 32
8.1 E25 (220 - 240V)
8.2 E25 (110V)
8.3 E25B
9. SPARE PARTS ............................................................................................................. 36
IMPORTANT: MAKING ALTERATIONS MAY VOID WARRANTIES AND APPROVALS.
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10. ACCESSORIES / OPTIONS ......................................................................................... 37
11. PARTS DIAGRAM........................................................................................................ 38
11.1 Main Assembly - E25
11.2 Main Assembly - E25B
11.3 Control Panel Assembly - E25
11.4 Control Panel Assembly - E25B
12. SERVICE CONTACTS ................................................................................................. 44
APPENDIX A. DOUBLE STACKING KIT.............................................................................. 46
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MODEL: E25 / E25B
1. SPECIFICATIONS
48
47
(1.9)
FRONT
720
720
(28.4)
625
626
(24.6)
600
600
(23.6)
429
430
(16.9)
E
1
124
124
(4.9)
45
45
(1.75)
E
1
111
111
(4.4)
395
395
(15.5)
SIDE
E
1
PLAN
LEGEND
- Electrical connection entry point
Dimensions shown in millimetres.
Dimensions in inches shown in brackets.
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LOCATION
To ensure correct ventilation for the motor and
controls the following minimum installation
clearances are to be adhered to:
Rear 25mm / 1”
Left-hand side 25mm / 1”
Right-hand side 25mm / 1”
OVEN INTERNAL DIMENSIONS
Width 470 mm / 18.5”
Height 254 mm / 10.0”
Depth 420 mm / 16.5”
Oven Volume 0.05 m³ / 1.75 ft³
OVEN RACK SIZE
Width 460 mm / 18”
Depth: 370 mm / 14.5”
ELECTRICAL SUPPLY SPECIFICATION
OPTIONS
E25
100-120V ac, 60Hz, 13.3A, 1.6kW @ 120V
220-240V ac, 50/60Hz, 8.5A, 2.05kW @ 240V
E25B
100-120V ac, 60Hz, 17.1A, 2.05kW @120V
ELECTRICAL PLUG SPECIFICATION
REQUIREMENTS
E25
Australia 3-pin 250V 10A, AS/NZ 3112
Canada 3-pin 120V 15A, NEMA 6-15
New Zealand 3-pin 250V 10A, AS/NZ 3112
United Kingdom 3-pin 250V 13A fused, BS
1363A
United States 3-pin 120V 15A, NEMA 6-15
Other Countries 3-pin 250V 10A minimum,
type to meet country stan-
dards
E25B
Canada 3-pin 120V 20A, NEMA 6-20
United States 3-pin 120V 20A, NEMA 6-20
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2. INSTALLATION
WARNING: THIS APPLIANCE MUST BE GROUNDED.
WARNING: ALL INSTALLATION AND SERVICE REPAIR WORK MUST BE CARRIED
OUT BY QUALIFIED PERSONS ONLY.
It is most important that the oven is installed
correctly and that the operation is correct
before use. Installation shall comply with local
electrical, health and safety requirements.
BEFORE CONNECTION TO POWER
SUPPLY
Unpack and check unit for damage and report
any damage to the carrier and dealer. Report
any deficiencies to your dealer. Check that
the available power supply is correct to that
shown on the rating plate located on the righthand side panel.
E25
100-120V ac, 60Hz, 13.3A, 1.6kW @ 120V
220-240V ac, 50/60Hz, 8.5A, 2.05kW @ 240V
E25B
100-120V ac, 60Hz, 17.1A, 2.05kW @120V
LOCATION
To ensure correct ventilation for the motor,
and controls the following minimum
installation clearances are to be adhered to:
Rear 25mm / 1”
Left-hand side 25mm / 1”
Right-hand side 25mm / 1”
BEFORE USE
Operate the oven for about 1 hour at 200°C
(400°F) to remove any fumes or odours which
may be present.
ELECTRICAL CONNECTION
E25 convection ovens are supplied with
pre-fitted cords. Ensure unit is fitted with the
correct cord and plug for the installation.
Refer specifications section.
Should changing of the cord be necessary,
gain access to the electrical connection
terminal block, grounding lug, and strain relief
by removing the back panel (four screws).
L1 L2
Phase
RED
BROWN
BLACK
WARNING:
Neutral
BLACK
BLUE
WHITE
THIS APPLIANCE MUST
BE GROUNDED / EARTHED
Ground
GREEN
GREEN/YELLOW
Figure 2.1
RATING PLATE LOCATION
The rating plate for the E25 convection oven
is located at the bottom left corner of the RH
side panel.
IMPORTANT: THE OVEN VENT
LOCATED ON THE CABINET TOP
MUST NEVER BE OBSTRUCTED.
Position the oven in its allocated working
position. Use a spirit level to ensure the oven
is level from side to side and front to back. (If
this is not carried out, uneven cooking could
occur). The feet used with bench mounting or
provided with stands are adjustable and will
require adjusting in levelling the unit. It should
be positioned so the operating panel and oven
shelves are easily reachable for loading and
unloading.
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Rating Plate
Figure 2.2
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3. OPERATION
NOTE: A full user’s operation manual is supplied with the product and can be used for further
referencing of installation, operation and service.
3.1 DESCRIPTION OF CONTROLS - E25
1. POWER
Depress to switch power on or off (switch
illuminates when power is on).
2. THERMOSTAT
1
2
Temperature range 50 - 250°C (120 - 480°F).
Indicator illuminates when elements are cycling
ON to maintain set temperature.
3. BAKE TIMER
1 Hour bake timer.
(Indicator illuminates when “time up” (0)
reached, and buzzer sounds).
4. LIGHT SWITCH
Push switch to activate light.
(Oven light illuminates while button depressed).
3
4
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3.2 DESCRIPTION OF CONTROLS - E25B
1. POWER
Depress to switch power on or off (switch
illuminates when power is on).
2. THERMOSTAT
1
2
Temperature range 50 - 270°C (120 - 525°F).
(Indicator illuminates when elements are cycling
ON to maintain set temperature.
BROIL POSITION (E25B Only) - The BROIL
indicator will illuminate indicating that the
BROIL function has been set. The HEATING
indicator will also illuminate whenever the elements are on.
3. BAKE TIMER
1 Hour bake timer.
(Indicator illuminates when “time up” (0)
reached, and buzzer sounds).
4. LIGHT SWITCH
Push switch to activate light.
(Oven light illuminates while button depressed).
3
4
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3.3 EXPLANATION OF CONTROL
SYSTEM
The E25 and E25B 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.
NOTE:
side of the heating element power relay on
E25B models whenever the electrical supply
is on.
With the power switch On (illuminated) power
is directly supplied to the 60 minute bake
timer, door microswitch, temperature control
circuit, 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 E25 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 door microswitch on the E25B oven
however, controls the light, the circulation fan,
and the fan element. Hence, opening the
door on the E25B oven causes the circulation
fan and fan element to switch off, as well as
causing the oven light to come on. (The broil
function incorporated into the E25B oven
requires the fan to be inoperative when
broiling with the door open).
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
The supply voltage is fed to the input
a capillary type thermostat which can be set to
a required cooking temperature. The E25B
also features a Broil position to provide top
browning or broiling in the oven.
The E25 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 E25B features a Broil element (located in
the top of the oven) as well as the fan
element. The thermostat switch has a
separate switch assembled onto the front of
the shaft assembly. This auxiliary switch,
depending on the thermostat setting, selects
between the fan or broil elements, via a Broil
relay located at the rear of the oven. A
changeover contact on the broil relay
determines which element is provided with
power. In series with the broil relay is a
second relay which is controlled by the main
thermostat switch. This is the heating relay.
One pole of the heating relay switches power
to the fan element, the other pole switches
power to the broil element. When the
thermostat cycles, both poles are switched
open or closed at the same time. However,
since only one pole is being fed power by the
broil relay, only the selected element cycles
on.
When the E25B thermostat is set to a cooking
temperature, one set of auxiliary switch
contacts remain open. This isolates power
from the coil of the two pole broil relay. In this
state the normally closed contacts of the first
pole provide power directly from the phase
connection on the terminal block to the fan
element pole on the heating relay. (The
normally closed contact on the second pole is
unused with this thermostat setting). The
second set of auxiliary switch contacts is
closed to feed power from the door
microswitch to the main thermostat switch.
When the thermostat cycles on it in turn feeds
power to the coil of the heating relay, causing
the changeover poles to switch. This closes
the normally open contacts and provides
power to the fan element. When the
thermostat cycles Off it isolates power to the
heating relay coil. This causes the normally
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open contacts to reset, thus switching the fan
element off. The control panel indicator light
above the thermostat knob cycles on and off
with the thermostat to indicate when the
elements are on and the oven is heating.
When the E25B thermostat is set to the Broil
position the first set of auxiliary switch
contacts close and the second set open. The
closed contacts provide power to the coil on
the Broil relay. The opened contacts isolate
power from the door microswitch to the main
thermostat switch. With the thermostat in this
setting, power to the coil of the broil relay
causes the changeover contacts on both
poles to switch. The normally closed contacts
of the first pole on the Broil relay open,
isolating power to the fan element. The
normally open contacts of this pole close
providing power instead to the broil element
(via the heating relay). Switching of the
second pole of the Broil relay closes the
normally open contacts, providing power
directly to the main thermostat switch. (This
alternate power supply to the thermostat
allows the Broil element to continue to operate
with the oven door open and fan off). When
the thermostat cycles On it provides power to
the coil of the heating relay. When the
heating relay switches, the normally open
contacts on both poles close. However, with
the thermostat in this position, power is only
being provided to the pole feeding the broil
element so only the broil element cycles On.
When the thermostat cycles Off it isolates
power to the heating relay coil. This causes
the normally open contacts to reset, thus
switching the broil element off again. With the
door closed the broil element will cycle On/Off
thermostatically at 600°F as this is the
thermostat setting in the Broil position. With
the door open the broil element will remain on
continuously and the circulation fan will be
turned off. The main heating indicator will
cycle on and off with the thermostat and broil
element, whilst the broil indicator will remain
illuminated as long as the thermostat is in the
Broil setting.
The following Troubleshooting Guide (pg 13)
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.
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4. MAINTENANCE
WARNING: ALL INSTALLATION AND SERVICE REPAIR WORK MUST BE CARRIED
OUT BY QUALIFIED PERSONS ONLY.
4.1 CLEANING
WARNING: ALWAYS TURN THE
POWER SUPPLY OFF BEFORE
CLEANING.
IMPORTANT: THIS UNIT IS NOT
WATER PROOF.
DO NOT USE A WATER JET SPRAY TO
CLEAN INTERIOR OR EXTERIOR OF
THIS UNIT.
EXTERIOR
Clean with a good quality stainless steel
cleaning compound. Harsh abrasive cleaners
may damage the surface.
INTERIOR
Ensure that the oven chamber is cool. Do not
use wire brushes, steel wool or other abrasive
materials. Clean the oven regularly with a
good quality oven cleaner. Take care not to
damage the fan or the tube at the right side of
the oven which controls the thermostat.
OVEN RACKS
To remove, slide out to the stop position, raise
the front edge up, and lift out.
BOTTOM BAFFLE
To remove, lift up the tray at the front finger
hole and pull forward out of the oven.
SIDE RACKS
Undo the thumbscrew (anti-clockwise rotation)
securing rack to oven wall, swing rack towards centre of oven to disengage location
pin at front of side, and pull rack forward to
remove. To replace, engage rack in rear
holes, swing towards side of oven to engage
in front hole, and replace thumbscrew.
FAN BAFFLE
To remove, undo thumbscrew (anti-clockwise
rotation) at top of baffle and remove. Lift baffle out from rear of oven by tilting forward
while lifting out of location studs at baffle
base. Replace in reverse order.
OVEN SEALS
To remove, hold at their centre point and pull
forward until they unclip. Remove side seals
first, then top and bottom. The seals may be
washed in the sink, but take care not to cut or
damage them. To replace the top seal,
ensure that the lip is facing the oven opening.
The left, right and bottom seals have the lip
facing out. Fit the top and bottom seals first,
then the side seals.
OVEN DOOR GLASS
Clean with conventional glass cleaners
4.2 ROUTINE PROCEDURES
DOOR SEALS
Check for deterioration 12 months
ELEMENTS
Check that element resistances
12 months
are correct to their ratings (refer
6.3.9)
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5. TROUBLE SHOOTING
WARNING: ALL INSTALLATION AND SERVICE REPAIR WORK MUST BE CARRIED
OUT BY QUALIFIED PERSONS ONLY.
FAULT POSSIBLE CAUSE REMEDY
THE OVEN DOES NOT
OPERATE / START
FAN DOESN’T OPERATE Door not closed (E25B only).
The mains isolating switch on
the wall, circuit breaker or fuses
are “off” at the power board.
The power switch on the oven is
off.
Incorrect electrical supply.
(Refer fault diagnosis 6.1.1)
Power switch on unit faulty.
(Refer fault diagnosis 6.1.1)
Door microswitch out of adjustment (E25B only).
(Refer fault diagnosis 6.1.2)
Door microswitch faulty (E25B
only).
(Refer fault diagnosis 6.1.2)
Fan motor faulty.
(Refer fault diagnosis 6.1.2)
Wiring.
Turn on.
Depress switch. Switch will
illuminate.
Ensure electrical supply correct.
Replace.
(Refer service section 6.3.4)
Close door.
Adjust.
(Refer service section 6.4.3)
Replace.
(Refer service section 6.3.2)
Replace.
(Refer service section 6.3.11)
Check and tighten any loose
wiring.
OVEN LIGHT NOT
ILLUMINATING - DOOR OPEN
OVEN LIGHT NOT
ILLUMINATING - DOOR
CLOSED
60 MINUTE TIMER WILL NOT
TIME DOWN
60 MINUTE TIMER
INACCURATE BELOW 20
MINUTES
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Blown bulb.
No power to light.
(Refer fault diagnosis 6.1.3)
Blown bulb.
Light switch faulty.
(Refer fault diagnosis 6.1.4)
Timer faulty.
Timer not set correctly.
Zero (time up) position not set
correctly.
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Replace.
(Refer service section 6.3.1)
Correct fault.
Replace.
(Refer service section 6.3.1)
Replace.
(Refer service section 6.3.4)
Replace.
(Refer service section 6.3.6)
For timer settings below 20 minutes, always rotate past 20 minutes, then back to desired time.
(Refer service section 6.4.4)
FAULT POSSIBLE CAUSE REMEDY
60 MINUTE TIMER NO TIME
UP BUZZER
60 MINUTE TIMER NO TIME
UP INDICATOR
NO HEAT No power to thermostat.
NO TEMPERATURE
CONTROL
Buzzer faulty.
(Refer fault diagnosis 6.1.5)
Timer not switching on buzzer.
(Refer fault diagnosis 6.1.5)
Indicator faulty.
(Refer fault diagnosis 6.1.6)
(Refer fault diagnosis 6.1.7)
Thermostat faulty.
(Refer fault diagnosis 6.1.7)
Fan element not working.
(Refer fault diagnosis 6.1.10)
Heating relay faulty - E25B only.
(Refer fault diagnosis 6.1.7)
Thermostat faulty.
(Refer fault diagnosis 6.1.8)
Heating relay faulty - E25B only.
(Refer fault diagnosis 6.1.8)
Replace.
(Refer service section 6.3.5)
Replace timer.
(Refer service section 6.3.6)
Replace.
(Refer service section 6.3.3)
Identify fault and correct.
Replace.
(Refer service section 6.3.7)
Correct element fault.
(Refer Fault: Fan element)
Replace.
(Refer service section 6.3.8)
Replace.
(Refer service section 6.3.7)
Replace.
(Refer service section 6.3.8)
SLOW RECOVERY Overloading of oven.
Electrical supply incorrect.
Fan not working.
Thermostat calibration.
(Refer fault diagnosis 6.1.9)
FAN ELEMENT NOT
WORKING
NO THERMOSTAT HEATING
INDICATOR LIGHT
Element faulty (blown).
(Refer fault diagnosis 6.1.10)
Faulty thermostat.
(Refer fault diagnosis 6.1.10)
Heating relay faulty - E25B only.
(Refer fault diagnosis 6.1.10)
Broil relay faulty - E25B only.
(Refer fault diagnosis 6.1.10)
Indicator faulty.
(Refer fault diagnosis 6.1.11)
Reduce oven loading.
Check supply voltage is as per
rating plate voltage.
Check fan operation.
Correct calibration.
(Refer service section 6.4.1,
6.4.2)
Replace.
(Refer service section 6.3.9)
Replace.
(Refer service section 6.3.7)
Replace.
(Refer service section 6.3.8)
Replace.
(Refer service section 6.3.8)
Replace.
(Refer service section 6.3.3)
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FAULT POSSIBLE CAUSE REMEDY
BROIL ELEMENT NOT
WORKING (E25B ONLY)
NO BROIL INDICATOR LIGHT
(E25B ONLY)
OVEN OVERHEATS IN BROIL
MODE—DOOR SHUT (E25B
ONLY)
DOOR DOES NOT CLOSE Tray in way of door.
Element faulty / blown.
(Refer fault diagnosis 6.1.12)
Faulty thermostat.
(Refer fault diagnosis 6.1.12)
Heating relay faulty
(Refer fault diagnosis 6.1.12)
Broil relay faulty
(Refer fault diagnosis 6.1.12)
Indicator faulty.
(Refer fault diagnosis 6.1.13)
Faulty heating relay.
(Refer fault diagnosis 6.1.14)
Door seal obstruction.
Door hinges worn.
Door hinge counter brackets
worn.
Replace.
(Refer service section 6.3.9)
Replace.
(Refer service section 6.3.7)
Replace.
(Refer service section 6.3.8)
Replace.
(Refer service section 6.3.8)
Replace.
(Refer service section 6.3.3)
Replace.
(Refer service section 6.3.8)
Correctly position tray in rack.
Correctly install door seal.
(Refer service section 6.3.14)
Replace.
(Refer service section 6.3.16)
Replace.
(Refer service section 6.3.17)
DOOR SEAL LEAKS Door seal damaged.
Door seal incorrectly fitted.
POWER SWITCH DOES NOT
SWITCH UNIT OFF
Power switch faulty.
(Refer fault diagnosis 6.1.15)
Broil relay faulty (E25B only).
(Refer fault diagnosis 6.1.15)
Heating relay faulty (E25B
only).
(Refer fault diagnosis 6.1.15)
Replace.
(Refer service section 6.3.14)
Correctly install door seal.
(Refer service section 6.3.14)
Replace.
(Refer service section 6.3.4)
Replace.
(Refer service section 6.3.8)
Replace.
(Refer service section 6.3.8)
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