Merrychef EC501, EC502 Service Manual

Merrychef

Mealstream 500

SERVICE MANUAL

Part No. 32Z3387 Issue No.3

For all Mealstream 501, 502 & 503 models manufactured

from January 2001 & Tim Hortons Models

CAUTION MICROWAVE EMISSIONS

DO NOT BECOME EXPOSED TO EMISSIONS FROM THE MICROWAVE

GENERATOR OR PARTS CONDUCTING MICROWAVE ENERGY

SERVICE MANUAL

Page 1 Mealstream Ovens 32Z3387 Issue 3

Table of Contents

Safety Code...........................................................................3

Product Specifications...........................................................4

Installation Instructions..........................................................5

Error Codes and Diagnostics.................................................6

Main Features........................................................................7

Electronic Controls ................................................................8

Manual Controls ....................................................................9

Power Output Testing to EN 60335-2-90 ............................10

Power Output Testing..........................................................11

Power Transformer Test......................................................11

High Voltage Capacitor Test................................................12

High Voltage Rectifier Test............... ... ... .............................12

Magnetron Test ...................................................................12

Principal components LHS..................................................13

Principal components RHS..................................................14

Principal components Top...................................................15

Principal components Cavity Roof and Door.......................16

Principal components Cavity...............................................17

Principal components ( not shown in main views ) .............18

Input wiring..........................................................................19

Interlock Operation..............................................................20

Electronic Control Panel Assembly .....................................21

Manual Controls Panel Assembly........................................22

Membrane Panel Circuit......................................................23

Complete Spare Part Listing.......................................... 24-25

Electrical Diagrams ....................................................... 26-27

Appendix 1: MenuKey Download Procedure..................... ..28

Appendix 2: Cleaning procedure...... ............................. 29-30

Appendix 3: PCB Connection Points............................. 31-33

Appendix 4: Transformer upgrade..................... ... ... ............34

Appendix 5 Hot air motor replacement......................... 35-39

Appendix 6: Temperature sensor replacement ...................40

Appendix 7: Fuse change FLM020 Type....................... 41-42

Appendix 8: Tim Hortons .............................................. 44-47

Appendix 9: Door interlock set-up procedure ................ 48-52

Manual corrections and modifications.................................53

Merrychef Limited,
Station Road West,
Ash Vale, Aldershot
Hampshire GU12 5XA
United Kingdom
Tel: [phone] Fax: [phone]
Internet address: http://www.merrychef.com
E-mail: [e-mail] or [e-mail]

Page 2 Mealstream Ovens 32Z3387 Issue 3

SAFETY CODE

This manual is designed to assist engineers who have been on a recognised product familiarisation
and training course run by Merrychef Limited. It has been prepared to offer technical guidance f or the
Merrychef Mealstream 501 range of Combination Microwave Ovens.

Please remember that it is wiser not to attempt a service task if you are unsure of being able to
complete it competently, quickly, and above all safely.

To avoid injury to yourself, and to protect the appliance from possible damage, please follow this
Safety Code when servicing these ovens.

Before attempting to repair the oven, check it for microwave leakage.
Check that the oven is not emitting microwaves, even when supposedly not in

operation.
Check that the oven is not operating continuously, whether the display indicates

cooking or not.
Always discharge the HT capacitors before working on the oven using a suitably

insulated 10 MΩ Resistor

Before removing the rear cover from the oven, ensure you do the following:

• Switch off the mains supply and remove the plug from the wall socket.

or

• If the oven is hard wired, ensure that the power is turned off at the isolator switch.

Note:

The On/Off switch on the oven is not adequate protection against electric

shock, as it does not isolate all of the internal wiring from the mains.

Upon completion of a service on a Mealstream oven, or before reconnecting the appliance to the
mains supply for testing, check all of the following points:

• All internal electrical connections are correct (see wiring diagram Pages 26-27).

• All wiring insulation is correct and is not touching a sharp edge.

• All Earth connections are electrically and mechanically secure.

• All door safety interlocks are secure and mechanically sound.

• The door operation is smooth, and the arms run freely in the slots.

• The door activates all three of the door interlock switches in the correct order.

• The temperature sensor is correctly connected to the Power PCB.

Before finishing the service call, recheck the following points:

• All of the electronics are functioning correctly, and all of the touch pads are working.

• The power output of the oven is correct.

• Microwave emission is below permissible limit - 5 mW/cm² (see BS EN 60335-2-90).

• Oven has correct 50mm air gap all round and 50mm above.

Air flow should not be restricted.

• Clean air filters are in place.

Page 3 Mealstream Ovens 32Z3387 Issue 3

Product specifications:

Model Number: CTMx v f c p MK C

Example CTM524505MK

Mealstream EC501, High speed fan
230-240V, 50Hz, Series 5 electronic controls & MenuKey

CTMx
Fan Speed

CTM3 =

Low speed
CTM5 =
High speed

Power
Requirements

Power Output:
CTM3

CTM5

External
Dimensions

Internal
Dimensions

v
Voltage

22 = 220-230V EU
24 = 230-240V UK

Refer to rating Plate

Microwave 100%
Convection
Combination
Convection
Combination

Height
Width
Depth

Height
Width
Depth
Capacity

f
Frequency c Control Type p Phase

50 = 50 Hz
60 = 60 Hz

5 = Electronic

CD2 = Rotary Dial

Controls

2 = 2 phase
1 = 1 phase

Omitted

1425W (IEC 705)
2500W
1425W + 2500W
3000W
1425W + 3000W

640mm (Plus 50mm minimum cleara nc e ab ove)
710mm (Plus 50mm minimum clearance each side)
630mm (Plus 50mm clearance behind)

260mm
490mm
360mm

45.86 litres (1.62 ft³)

MK
MenuKey

MK =

MenuKey
fitted

C
Catalytic
Converter

C=

EC503
Catalytic
Converter

Weight Nett

Gross packed

Construction Cavity

Casework

Settings Microwave

Temperature
Timer

90kg
106kg

304 Stainless Steel

100%,75%,50%,25%, Convection only
Off, 150°C, 175°C, 200°C, 225°C, 250°C
Up to 30 minutes
Up to 3 cooking stages of up to 30 minutes each
Programmed (Series 5)

Page 4 Mealstream Ovens 32Z3387 Issue 3

Installation instructions:

Installation Instructions for Mealstream 500 series Combination Ovens

Power Supply Requirements

The Mealstream 500 series oven should be connected to a suitable electricity supply, which
can cope with the switching-on surge that occurs with certain types of catering equipment, such
as microwaves. Because of this requirement, we strongly recommend that a separate, suitably
rated supply is installed for the oven.

The supply for the oven should be fitted with a Type "C" circuit breaker, rated at:
30 Amp for Mealstream 500 Series (all models)
If the oven is hard-wired to the supply, a double-pole isolator switch with a contact gap of at

least 3mm should be fitted and positioned close to the oven to allow the oven to be moved for
servicing.

Positioning the Oven
In order to maintain adequate ventilation for air intake and exhaust, and to allow access for

cleaning filters, you must allow a minimum of 50mm clearance at the sides and rear of the
oven, and at least 50mm above. Air intake temperature should not exceed 35°C - excessive
temperature will lead to reduced operating duty cycle or premature ageing of internal
components.
Failure to comply with these conditions will invalidate the warranty.

NEVER Install an oven above fryers, grills, griddles or any other major heat source.
NEVER Stack machines on top of each other - always use a double stand.

ALWAYS Place containers in the cavity carefully - impact damage may chip the

vitreous enamel coating on the runners and baffle plate.

50mm 50mm

50mm

50mm

350mm

Page 5 Mealstream Ovens 32Z3387 Issue 3

Error codes and diagnostics

Models with electronic controls identify some of the most common problems by flashing an
error message code in the time display window.

Error Message

1

1

1 Oven Cavity overheating Check cavity sensor

Possible Cause Service

Door not fully shut

2

Possible electrical fault

No time has been set
Invalid time has been set

2

Invalid program has been set

3

Number pad failure

4

Memory Failure running a

5

Program
Oven not heating up

1

Possible Heater circuit fault

2

Close door fully
Check Microswitch Door Circuit

Check Microswitch Connection to PCB
Check Ribbon Cable
Check Relay PCB & Logic PCB

Set a time
Set a valid time
Use call-back to check program
(MenuKey: no key downloaded)
Membrane key short circuit
Re-Program Pad,
if fault repeats replace Logic PCB

Check heater fuse
Confirm operation of heater, overheat

stat and heater circuit

Confirm heater relay is operating

1 Oven is not at correct

temperature to start program
Operator Error !!

1 Oven control area is

overheating.

MenuKey removed before the

download is complete
or the process has been
interrupted.

Allow oven to reach correct
Programmed temperature

Check air filters
Check axial fan
Check installation for hot air intake

Switch oven off and begin the MenuKey
download again.

Page 6 Mealstream Ovens 32Z3387 Issue 3

Main features:

m

g

j

back panel

a

b

c

d

e

k

l

b

f

k

i

h

a On/Off SWITCH

This is used to turn the oven On or Off.

IT DOES NOT IS OLATE INTERNAL WIRING
FROM THE MAINS SUPPLY.

b HOT AIR VENTS

Allows steam and excess pressure to escape

from the oven cavity. It must be kept clear.

c OVEN CAVITY

The oven cavity is mainly constructed from
stainless steel panels. It must be kept clean.

d BAFFLE PLATE

EC501 Models:
The convection fan draws air over the heating
element into the cavity ove r the edges of the rear
baffle plate producing perfect heat distribution for
combination cooking. The metal grill covering the
fan must be kept clean and free of debris.
502 & 503 Models:
The convection fan, which is located behind the
cavity filter pulls air in through the catalytic
converter which removes the majority of the smoke
from the air flow.

e RUNNERS

These are mounted on each side of the oven
cavity to support the rectangular racks or oven
trays and are for use in Convection mode
only.

f HOT AIR FAN

Situated behind the baffle plate, and circulates
the hot air through the baffle plate, over the
heating element, and around the edge of the
baffle plate back into the cavity.
CTM3_ Low speed Fan
CTM5_ High Speed Fan

g RATING PLATE

The rating plate is situated on the rear of the
oven, and states the Model, Serial Number,
Electrical Ratings and Manufacturers telephone
number.

h DOOR

The door consists of a thermally insulated inner
section, and an additional air gap provided by a
twin skinned door front to lower the surface
temperature.
It is important that the choke plate and the slots
are free from debris.

i DOOR SEAL
j MAINS LEAD

k AIR FILTERS

Main intake for cooling air for internal
components. Must be clear of obstructions.

l MenuKey

m STEAM OUTLET

Page 7 Mealstream Ovens 32Z3387 Issue 3

Electronic controls:

j

i

h

g

a

b

f

d

c

e

k

a Stage LED's
b Program & Time Display
c Service Indicator
d Air Filter Block Indicator
e Convection Pad

f Power Pads
g Time / Program Number Pads
h Temperature Set Pads

i Cancel / Callback Pad

j Program Pad
k MenuKey socket

Page 8 Mealstream Ovens 32Z3387 Issue 3

Manual controls:

merrychef

a

b

c d

POWER %TEMP °C

TIME

e

START

f

Mealstream CD

2

g

a Power Neon ( Amber )
b Temperature Control
c Power Control
d Timer
e Start Push button

f Cook cycle Neon ( Red )

g Heater Neon ( Amber )

Page 9 Mealstream Ovens 32Z3387 Issue 3

Procedure A - Power Output Test in accordance with
BS EN 60335-2-90 Annex AA

This test is given in the BSI test standard for microwave ovens. It is reproduced belo w - not so that
you can follow it, but to show you why it is impractical in normal conditions. A simplified procedure,
which gives a good approximation to the BSI power output, is given in Procedure B which follows.

Note: This test can only be carried out on a COLD oven. If the oven has been operating, even for
only a few seconds, the power given will be lower than the oven rating. This test must also be carried
out at a stable voltage - the voltage in most kitchens varies considerably even within the period of the
test. If the oven has been operating, go to Procedure B.

You will need:

A thermometer capable of reading to ±0.1°C.
A cylindrical borosilicate glass container, 190 mm diameter, with a wall thickness of

3 mm or less.

A calculator.
A set of scales capable of reading 1kg to an accuracy of ± 1g.
A glass or plastic stirrer.
A jug capable of holding over 1 litre of water.
Drinkable water which is at a temperature of 10°C ± 1°C.
A “Variac” or similar variable transformer capable of supplying the oven to ensure a

stable voltage.

WARNING: The Borosilicate Glass container has thin walls and is therefore fragile

- take care not to break it during use.

Method
A cylindrical container of borosilicate glass is used for the test. It has a maximum thickness of
3mm, an external diameter of approximately 190mm and a height of approximately 90mm. The
mass of the container is determined.

At the start of the test, the oven and the empty container are at ambient temperature. Potable water
having an initial temperature of 10°C ± 1°C is used for the test. The temperature of the water is
measured immediately before it is poured into the container.

A quantity of 1000g ± 5g of water is added to the container and its actual mass obtained. The
container is then immediately placed in the middle of the oven base. The appliance is supplied at
rated voltage and operated at the maximum power setting. The time for the water temperature to
attain 20°C ± 2°C is measured. The oven is then switched off and the final water temperature is
measured within 60seconds.

NOTES:

1 The water is stirred before its temperature is measured.
2 Stirring and measuring devices are to have a low heat capacity.

The microwave power output is calculat e d from the formula:

4.187 M

(T2-T1) + 0.55 MC (T2-T0)

W

P =
t
where

P is the microwave power output, in watts;
M

is the mass of the water, in grams;

W

M

is the mass of the container, in grams;

C

T

is the ambient temperature, in °C;

0

T

is the initial temperature of the water, in °C;

1

T

is the final temperature of the water, in °C;

2

t is the heating time in seconds, excluding the magnetron filament heat-up time.

Page 10 Mealstream Ovens 32Z3387 Issue 3

Procedure B - Simplified Power Output Test

You will need:

A thermometer capable of reading to ±0.1°C.
A Polypropylene tray approximately 200 mm x 200 mm.
A measuring jug.
A calculator.
Water which is at a temperature of 10°C ± 2°C.

1 Measure 1 litre of cold water into the tray using the measuring jug.
2 Measure the water temperature, and record it as T[s].
3 Place the tray in the oven and close the door.
4 Turn the oven on.
5 Set the timer to 1:02. ( For Manual controls use a stopwatch set to 1 minute 2 seconds )
6 Press the “100%” power pad.
7 When the oven bleeps, open the door and remove the tray.
8 Stir the water thoroughly, and measure its temperature. Record this as T[e].

Calculation:

1 T[r] = T[e] - T[s].
2 Power = 70 x T[r]. Power is in Watts.

The power given by the above test should be within ±10% of the rated power.

For Tim Hortons
see APPENDIX 8

Procedure C - Power Transformer Test

You will need:

A Digital Multi-meter (D.M.M.)
A Megger or similar resistance meter using 500V d.c.

1 Isolate the oven from the mains supply.

WARNING: High voltages and large currents are present at the secondary winding and filament

winding of the Power Transformer. It is very dangerous to work near this part when the
oven is on. NEVER make any voltage measurements at the High Voltage circuits,
including the magnetron filament.

WARNING: Even when the oven is n ot cooking, the Power Transformer has High Voltages present

because of the Soft Start circuit. Isolate the oven before testing.

2 Ensure that the High Voltage Capacitor is discharged before commencing work.
3 Remove all connections from the Power Transformer.
4 Using a D.M.M., check the continuity of the windings. Results should be as follows:

a Mains winding between tags
b High Voltage winding
c Filament winding

between terminals

Approx. 1.3 Ω
Approx. 82 Ω
Less than 1 Ω

c

b

5 Using a Megger, test the insulation resistance between:

Primary winding and chassis
Filament winding and chassis

One end of the High Voltage winding is connected to the

chassis, so this is not tested.

Pass if over 10 MΩ
Pass if over 10 MΩ

a

Page 11 Mealstream Ovens 32Z3387 Issue 3

Procedure D - High Voltage Capacitor Test

You will need: A Digital Multi-meter (D.M.M.)

A Megger or similar resistance meter using 500V d.c.

WARNING: High voltages and large currents are present at the High Voltage Capacitor. It is very

dangerous to work near this part when the oven is on. NEVER make any voltage
measurements at the High Voltage circuits, including the magnetron filament .

WARNING: Even when the oven is not cooking, the High Voltage Capacitor has High Voltages

present because of the Soft Start circuit. Isolate the oven before testing.

1. Isolate the oven from the mains supply.

2. Ensure that the High Voltage Capacitor is discharged before
commencing work.

3. Remove all connections from the High Voltage Capacitor.

4. Using a D.M.M., check for continuity between the terminals &

Between Terminals
Between Terminals and Case Pass if open circuit

5. Using a Megger, test the insulation resistance between the
terminals and the case.

Between Terminals and Case

Procedure E - High Voltage Rectifier Test

You will need:

A Megger or similar resistance meter using 500V d.c.

WARNING: High voltages and large currents are present at the High Voltage Rectifier. It is very

dangerous to work near this part when the oven is on. NEVER make any voltage

WARNING: Even when the oven is not cooking, the High Voltage Rectifier has High Voltages

1. Isolate the oven from the mains supply.

2. Ensure that the High Voltage Capacitor is

discharged before commencing work.

3. Remove all connections from the High Voltage

Rectifier.

4. Using the Megger, test for continuity in both

directions. Compare results with the table.

measurements at the High Voltage circuits, including the magnetron filament .

present because of the Soft Start circuit. Isolate the oven before testing.

Pass if approximately 10 MΩ

Pass if over 100 MΩ

Open Circuit both ways
Conducts one way only
Short Circuit both ways
Conducts one way, leaks the other

FAIL

PASS

FAIL
FAIL

Procedure F - Magnetron Test

You will need:

A Megger or similar resistance meter using 500V d.c.

A Magnetron can be tested for an open filament or a short circuit
by carrying out a continuity check.

1. Isolate the oven from the mains supply.

2. Ensure that the High Voltage Capacitor is discharged before

commencing work.

3. Remove all connections from the Magnetron.

4. A continuity check across the Filament terminals should be 1ohm or less

5. A continuity check between each filament terminal and the

metal outer should read open.

Page 12 Mealstream Ovens 32Z3387 Issue 3

Principle components:

Left side

1

1A

2

2A

3

3A

14

4A 4

13

12

6

11

7
8

10

9

No Description EC 501/2/3 RD 501

1 Fuse holder 30Z0231 30Z0231
1A Fuse 10 amp 30Z0217 30Z0217
2 Fuse holder 30Z0231 30Z0231
2A Fuse 10 amp 30Z0217 30Z0217
3 Fuse holder 30Z0231 30Z0231
3A Fuse 1 amp 30Z0957 30Z0957
4 Fuse holder 30amp ( FLM Series )B 30Z1178 30Z1178
4A Fuse 20 amp Littlefuse FLM020B 30Z1177 30Z1177
6 Mains terminal block 31Z0149 31Z0149
7 Filter ( Heater circuit ) 30Z0997 30Z0997
8 Filter ( Microwave circuit ) 30Z0997 30Z0997
9 Door spring short 520000 520000

9 Door spring long 40C1141 40C1141
10 Door arm stop assembly 11C0279 11C0279
11 Microswitch ( Primary ) 30Z0240 30Z0240
12 Door hinge assembly ( LH )A 11C0167 11C0167
13 Door arm assembly 11C0300 11C0300
14 Microswitch ( Monitor ) 30Z0240 30Z0240

Note A: see page 17 for parts
Note B: see appendix for models before March 2004

Page 13 Mealstream Ovens 32Z3387 Issue 3

Principle components:

Right side

13

22

21

20

16

No Description EC 501/2/3 RD 501

9 Door spring short

9 Door spring long
10 Door arm stop assembly
13 Door arm assembly
16 Door hinge assembly ( RH )A
17 Microswitch ( Secondary )
20 Steam pipe
21 Steam vent guard
22 Temperature sensorC

Note A: see page 17 for parts

Note C: see appendix for models before March 2004

17

9 10

520000 520000

40C1141 40C1141

11C0279 11C0279
11C0300 11C0300
11C0166 11C0166
30Z0240 30Z0240

790046 790046
790061 790061

50E123 50E123

Page 14 Mealstream Ovens 32Z3387 Issue 3

Principle components:

Top view

23

24

25

26

27

60 61

23

24

25

26

27

28

No Description EC 501/2/3 RD 501

23 Magnetron 30Z0264 30Z0264
24 Resist or Gold 470 R 30Z0283 30Z0283
25 HT diode 11C0266 11C0266
26 Capacit or 1. 1µF 30Z1077 30Z1077
27 Trans f o rmer 220 V 50Hz 30Z0083 30Z0083
27 Trans f o rmer 240 V 50Hz 30Z1018 30Z1018
28 Twin blower motor 310110 310110
60 25mm OD Flexible conduit 314402 314402
61 20mm OD Flexible conduit 314401 314401
62 Capacitor c lip 31Z0175 31Z0175

62

Page 15 Mealstream Ovens 32Z3387 Issue 3

Principle components:

Door & cavity roof

72

67

67a

71

Note: for Tim Hortons see Appendix 8

No Description EC 501/2/3 RD 501

67 Stirrer glass & long seals 40C0954 40C0954

67a Stirrer glass short side seal 790052 790052

71 Door seal kit 11C0292 11C0292

Air Filters

72 Door choke 790007 790007

81

No Description EC 501/2/3 RD 501

81 Air fi lt er panel (remov abl e) 40C0868 40C0868

81

Page 16 Mealstream Ovens 32Z3387 Issue 3

Principle components:

Heater Element, Catalytic Converter & Cavity parts:

CTM5_, [EC501]

74

68a

70

CTM5_, [EC503]

74

68a

78

78

77

69

76

CTM5_, [EC502]

74

68a

80

76

77

77

78

CTM3_
[EC501, RD501]

79

76

77

68

77

69

74

77

No Description Part No.

68 Heater element (2.5kW) 40C0954

68a Heater element (3.0kW) 40C0948

69 Heater element cover plate 790047
70 Baffle 11C0311
76 Dome Nut 80X7025
77 Shelf Support 40C0950
78 Hot Air Impeller MC3703B
79
80

Element cover plate Assembly
Element cover plate Assembly

11C0474
11C0467

Page 17 Mealstream Ovens 32Z3387 Issue 3

Principle components: ( not shown in main views )

Left Hand Door Hinge

12

Assembly

(Includes all parts shown)

54

53

Hot air motor:

57

Low Speed

Right Hand Door Hinge

16

Assembly

(Includes all parts shown)

52

52

51

51

55

55

54

53

Stirrer motor assembly

58

Hot air motor:

57

High Speed

Motor shaft screen
and seal assembly

50

49

No. Description EC501/2/3 RD501

12 Door Hinge Assembly LH 11C0167 11C0167
16 Door Hinge Assembly RH 11C0166 11C0166
49 Motor shaft screen 40C1005 40C1005
50 Hot air motor damper/seal 40C1008 40C1008
51 Pin 790027 790027
52 Roller 40C0752 40C0752
53 M5 Hex/hd s/s Screw 101825 101825
54 M5 stainless steel Nut 80X7003 80X7003
55 LH Hinge bracket 790024 790024
56 RH Hinge bracket 790025 790025
57 Hot air motor Low Speed [CTM3] 11C0161 11C0161
57 Hot air motor High Speed [CTM5] 11C0526 —–
58 Stirrer motor assembly 11C0162 11C0162

Page 18 Mealstream Ovens 32Z3387 Issue 3

Input wiring details

Green/Yellow

6

Blue

Brown

48

46 47

No Description

6 Main s Terminal Block 31Z0149
46 Cable Gland 31Z1070
47 Gland Nut 31Z1082
48 Mains Cabl e 3 Core 31Z0148

Part No.

High Speed Hot Air Motor [CTM5] connections and wiring

Page 19 Mealstream Ovens 32Z3387 Issue 3

Door interlock operation

The door on the oven is monitored by three microswitches. These are used in the
conventional “Primary, Secondary and Monitor” switch arrangement shown below.
The switches operate as follows:

Door Interlock Arrangement

L

Power In

N

The diagram shows the microswitches in door closed position

1. Primary Interlock [ 11 , Bottom left-hand ] and
Secondary Interlock [ 17 , Bottom right-hand ] Switches.
Operate simultaneously.
The Primary switch or Secondary switch will cut off the microwave emissions
from the oven when the door is opened by breaking the mains supply circuit to
the transformers.

2. Monitor [ 14 ,Top left-hand Side ]
The Monitor switch will produce a short circuit across the mains supply if the
Primary interlock switch is faulty, thus blowing the microwave fuse and rendering
the oven inoperative.
The Secondary interlock switch will cut off the microwave emission if the other
switches have failed.

Note:

If operation of the Monitor switch has caused the Microwave Fuse to blow, the

Primary and Monitor microswitches must be changed, as they may have been
damaged by the high short-circuit currents involved.

Primary switch

17 Secondary switch

11

Power Out

14 Monitor switch

Page 20 Mealstream Ovens 32Z3387 Issue 3

Electronic control panel assembly: EC501, EC502 & EC503

29

34

33

32

31

73

30

No Description
29 On/Off Switch 30Z0503
30 Control Panel Assembly (without MenuKey) 11C0294
30 Control Panel Assy with MenuKey 11C0438
30 Locare Control Panel Assy with MenuKey 11C0458
31 Logic Board (without MenuKey) 11C0291
31 Logic Board with MenuKey 11C0377
32 Relay Board 11C0212
33 AC Ribbon connector 11M0116
34 DC Ribbon connecto r 11M0117
73 MenuKey Assembly 10C0148

Part No.

Page 21 Mealstream Ovens 32Z3387 Issue 3

Manual control panel assembly: RD501

35

33

34

44

38

39

40

41

40

29

38

29

38

38

No Description

29 On /off switch 30Z0503
33 ac voltag e connector 6 way 11M0116
34 dc voltag e connector 10 way 11M0117
35 PCB Assembly 11C0295
38 Red Ne o n 316030
39 Timer 30Z0991
40 Potentio met er 5k 40C0892
41 Amber Neon 316031
43 Panel ass emb ly 11C0307
44 Pushbutton 31Z0349
45 Control knob Red/Grey 11C0173

41

Part No.

44

45

45 Control knob Blue 11C0406

Page 22 Mealstream Ovens 32Z3387 Issue 3

Membrane panel circuit

You will need:

A Digital Multi-meter (D.M.M.)

1. Isolate the oven from the mains supply.

2. Remove the Logic Assembly from the Control Panel Housing.

3. Unplug the membrane “tail” from the Logic PCB Assy.

4. Using a D.M.M., check for continuity between the correct terminals when the
pads are pressed.

5. When the panel has been tested, re-assemble and re-test the control housing.

1 10

Page 23 Mealstream Ovens 32Z3387 Issue 3

Part number identification chart:

No Description

1 Fuse holder 30Z0231 30Z0231

1a Fuse 10 amp 30Z0217 30Z0217

2 Fuse holder 30Z0231 30Z0231

2a Fuse 10 amp 30Z0217 30Z0217

3 Fuse holder 30Z0231 30Z0231
3a Fuse 1 amp 30Z0957 30Z0957
4 Fuse holder 30amp ( FLM Series )B 30Z1178 30Z1178
4A Fuse 20 amp Littlefuse FLM020B 30Z1177 30Z1177

6 Mains terminal block 31Z0149 31Z0149

7 Filter ( Microwave circuit ) 30Z0997 30Z0997

8 Filter ( Heater circuit ) 30Z0997 30Z0997

9 Door spring short 520000 520000

9 Door spring long 40C1141 40C1141
10 Door arm stop assembly 11C0279 11C0279
11 Microswitch ( Primary ) 30Z0240 30Z0240
12 Door hinge assembly ( LH ) 11C0167 11C0167
13 Door arm assembly 11C0300 11C0300
14 Microswitch ( Monitor ) 30Z0240 30Z0240
16 Door hinge assembly ( RH ) 11C0166 11C0166
17 Microswitch ( Secondary ) 30Z0240 30Z0240
20 Steam pipe 790046 790046
21 Steam vent guard 790061 790061
22 Temperature sensorC 50E123 50E123
23 Magnetron 30Z0264 30Z0264
24 Resistor Gold 470 R 30Z0283 30Z0283
25 HT diode 11C0266 11C0266
26 Capacitor 1.1 µF 50Hz 30Z1077 30Z1077
26 Capacitor 0.88µF 60Hz 30Z1075 30Z1075
27 Transformer 220V 50Hz 30Z1018 30Z1018
27 Transformer 240V 50Hz 30Z1183 30Z1183
27 Transformer 220V 60Hz 30Z1192 30Z1192
27 Transformer 240V 60Hz 30Z1191 30Z1191
28 Twin blower motor 310110 310110
29 On/Off Switch
30 Control Panel Assembly (without

Menukey)

30 Control Panel Assy with Menukey
30 Locare Control Panel Assy with

Menukey

31 Logic Board (without Menukey)
31 Logic Board with Menukey
32 Relay Board
33 AC Ribbon connector 6 way
34 DC Ribbon connector 10 way

EC501/2/3 RD501

30Z0503 30Z0503

11C0294 ———

11C0438 ———
11C0458 ———

11C0291 ———
11C0377 ———

11C0212 ———
11M0116 11M0116
11M0117 11M0117

Note B: see APPENDIX 7
for models before March 2004

Note C: see APPENDIX 6
for models before March 2004

Page 24 Mealstream Ovens 32Z3387 Issue 3

Part number identification chart:

No Description

35 PCB Assembly ——— 11C0295
38 Red Neon ——— 316030
39 Timer ——— 30Z0991
40 Potentiometer 5k ——— 40C0892
41 Amber Neon ——— 316031
43 Panel assembly ——— 11C0307
44 Pushbutton ——— 31Z0349
45 Control knob Red/Grey ——— 11C0173
45 Control knob Blue ——— 11C0406
46 Cable Gland 31Z1070 31Z1070
47 Gland Nut 31Z1082 31Z1082
48 Mains Cable 3 Core 31Z0148 31Z0148
49 Motor shaft screen 40C1005 40C1005
50 Hot air motor damper/seal 40C1008 40C1008
51 Pin 790027 790027
52 Roller 40C0752 40C0752
53 Bolt 101825 101825
54 Nut 80X7003 80X7003
55 LH Hinge bracket 790024 790024
56 RH Hinge bracket 790025 790025
57 Hot air motor Low Speed [CTM3] 11C0161 11C0161
57 Hot air motor High Speed [CTM5] 11C0526 ——
58 Stirrer motor assembly 11C0162 11C0162
60 25mm OD Flexible conduit 314402 314402
61 20mm OD Flexible conduit 314401 314401
62 Capacitor clip 31Z0175 31Z0175
67 Stirrer glass 40C0954 40C0954

67a Stirrer glass short side seal 790052 790052

68 Heater element 2.5kW —— 790063

68a Heater element 3.0kW 40C0948 ——

69 Baffle Plate 790047 790047
70 Baffle Side ( 2 No. ) 11C0311 11C0311
71 Door seal kit 11C0292 11C0292
72 Door choke 790007 790007
73 MenuKey Assembly

EC501/2/3 RD501

10C0148 ——

74 Mesh washer RFI gasket
75 Shelf support
76 Dome Nut
77 Shelf Support
78 Hot Air Impeller
79 Element cover plate Assembly
80 Element cover plate Assembly
81 Air filter panel (removable)
82 PCB stand off

31Z5044 31Z5044
40C0864 40C0864
80X7025 80X7025
40C0950 40C0950

MC3703B MC3703B

11C0474 11C0474
11C0467 11C0467
40C0868 40C0868

2243033 2243033

Page 25 Mealstream Ovens 32Z3387 Issue 3

Circuit diagram: EC501, EC502, EC503

Page 26 Mealstream Ovens 32Z3387 Issue 3

Circuit diagram: RD501, CTM3__CD2

Page 27 Mealstream Ovens 32Z3387 Issue 3

APPENDIX 1: MenuKey Download Procedure

The MenuKey™ System automatically changes all the cooking
programs on the numbered icon pads with the turn of a key.

To change the menus on the oven:

Ensure the power switch is off.

1

Lift the MenuKey cover in the

2

front panel of the oven and
put the key in the keyhole
Turn the key clockwise to the
stop ( ¼ turn ).
Do not rem ove the key at this
stage.

3

Switch the power switch on.
The oven will now go through the
program download sequence by
displaying the following:

The Key Code

example: Key C02

The number of programs and each
program number on the key.

example: 27 Programs

When the display shows 00:00.
Remove the key and close the co ver.

The oven is now ready to use with the
new programs.

To confirm the download is successful
Switch off the oven.
Switch on and the display briefly will show the following:

1. The new key code

2. 00:00 (oven ready to use)
If the download is not successful the key number will not be

displayed and if the program pads are pressed an E3 error will
display.

EPS - FAIL - REDO
External Program
System ERROR.

If the key is removed
before the download is
complete or the process is
interrupted the display
shows “EPS” then “FAIL”
then “REDO”. Switch the
oven off and begin the
MenuKey download again.

Page 28 Mealstream Ovens 32Z3387 Issue 3

APPENDIX 2: Cleaning procedure Mealstream 501

For the oven to operate at peak efficiency, the cavity, door and the air filters must be
kept clean.

A daily cleaning routine will ensure that you comply with the required hygiene standards
and will help to maintain and prolong the efficiency of your oven.
Follow the SAFETY INSTRUCTIONS at the beginning of this manual.

• ALWAYS switch off at the electrical supply and allow
oven to cool for at least 20 minutes before cleaning.

• As required, wipe out spillage's with disposable paper
wipes

• NEVER use steel wool, knives or harsh abrasives on
any part of the oven

As with all electrical appliances, it is wise to have the
electrical connections inspected periodically.

Cleaning the Air Filters

1 Remove the air filters from each side of the oven by

sliding the filter out from the front.

2 Wash in clean, warm soapy water, rinse and pat dry. Slide

back into position through slots.

Cleaning the oven cavi ty and door

1 Remove food particle s from the gap between the rear

baffle plate and the floor of the oven with a clean, dry
brush. ( Location A )
Remove food particles from between the inside edge of
the door and the front of the oven floor using a clean, dry
brush. ( Location B )

2 Apply non-caustic oven cleaner to interior surfaces

except door seals. Leave for the recommended time.
Wash off using a clean cloth and plenty of clean, warm
water. Dry using a fresh, clean cloth.

3 Wipe hinges with a clean, damp cloth.

DO NOT apply lubricating oil.

4 Wipe door seals carefully with a clean damp cloth.

Examine for signs of wear or damage.

Faults arising from neglect
or misuse including use
without clean filters in place
are not covered by the
guarantee. Service visits as
a result of such faults will be
chargeable.

DO NOT USE THE OVEN

WITHOUT CLEAN AIR

FILTERS IN POSITION

B

A

Door Seal

Cleaning the control panel and exterior surfaces

Wipe down regularly with a damp cloth.

Hints and Tips for st u bbor n s t a ins in the oven cavity

1 Switch on oven with microwave power only (without heat).
2 Place a container of water (1.5 litres) into the centre of the

oven cavity.
3 Set microwave power to 10 0 % .
4 Set timer to 30 minutes and press start button at end of

steam cycle wipe out cavity with a clean cloth.

If the door seals are damaged,
the oven must be repaired by an
approved Servicer.

Page 29 Mealstream Ovens 32Z3387 Issue 3

APPENDIX 2: Cleaning procedure Mealstream 502, Mealstream 503

For the oven to operate at peak efficiency, the cavity, door and the air filters must be
kept clean.

A daily cleaning routine will ensure that you comply with the required hygiene standards and
will help to maintain and prolong the efficiency of your oven.
Follow the SAFETY INSTRUCTIONS at the beginning of this manual.

• ALWAYS switch off at the electrical supply and allow

oven to cool for at least 20 minutes before cleaning.

• As required, w ipe out spillage's with disposable paper

wipes

• NEVER use steel wool, knives or harsh abrasives on

any part of the oven

As with all electrical appliances, it is wise to have the
electrical connections inspected periodically.

Cleaning the Air Filters

1 Remove the air filters from each side of the oven by

sliding the filter out from the front.

2 Wash in clean, warm soapy water, rinse and pat dry. Slide

back into position through slots.

Cleaning the ove n ca vity and door

1 Remove food particles from the gap between th e rear

baffle plate and the floor of the oven with a clean, dry

brush. ( Location A )

Remove food particles from between the inside edge of

the door and the front of the oven floor using a clean, dry

brush. ( Location B )

Do not spray any clea ning fluid
directly into the cavity filter

2 Apply non-caustic oven cleaner to interior surfaces except

door seals. Leave for the recommended time. Wash off
using a clean cloth and plenty of clean, warm water. Dry
using a fresh, clean cloth.

3 Wipe hinges with a clean, damp cloth.

DO NOT apply lubricating oil.

4 Wipe door seals carefully with a clean damp cloth.

Examine for signs of wear or damage.

Faults arising from neglect
or misuse including use
without clean filters in place
are not covered by the
guarantee. Service visits as
a result of such faults will be
chargeable.

DO NOT USE THE OVEN

WITHOUT CLEAN AIR
FILTERS IN POSITION

A

Door Seal

B

Cleaning the control panel and exterior surfaces

Wipe down regularly with a damp cloth.

Hints and Tips f or s t ubborn stains in the o ven cavity

1 Switch on oven with microwave power only (without heat).
2 Place a container of water (1.5 litres) into the centre of the

oven cavity.
3 Set microwave power to 100%.
4 Set timer to 30 minutes and press start button at end of

steam cycle wipe out cavity with a clean cloth.

If the door seals are damaged,
the oven must be repaired by an
approved Servicer.

Page 30 Mealstream Ovens 32Z3387 Issue 3

APPENDIX 3: PCB Connection Points and key features, EC501, EC502 & EC503

11C0291 Issue 5

Cavity sensor
50E123

Relay PCB

Relay PCB

°C Link

Page 31 Mealstream Ovens 32Z3387 Issue 3

APPENDIX 3: PCB Connection Points and key features EC501, EC502 & EC503

11C0377 Issue 2

Menukey

Temperature
Calibration

Relay PCB

Relay PCB

°C Link

Page 32 Mealstream Ovens 32Z3387 Issue 3

APPENDIX 3: PCB Connection Points and key features EC501, EC502 & EC503

11C0212 Issue 11
Relay PCB

Transformer 1 (LHS)

Transformer 2 (RHS)

Soft start common relay

Heater switch

Logic PCB Logic PCB

Return from door switch & 0H Mag stats

Neutral

Live

Earth

Page 33 Mealstream Ovens 32Z3387 Issue 3

APPENDIX 4: Transformer Upgrade

In partnership with our supplier Tabuchi, we have developed a multi-tap transformer that will
output 208V, 220V & 240V. There are 2 models for 50Hz and 60Hz power supply.

Should you need to change a transformer to any Mealstream 501 product, you should use the
new 30Z1233 ( 50Hz power supply ) or 30Z1230 ( 60Hz power supply) multi-tap transformer, see
matrix below.

Should you have an oven where just one transformer has failed, you can mix an old transformer
with a new transformer on the oven.

Note: The capacitor values remain the same when using the new 30Z1233 or 30Z1230 transformer.

Replacement Transformer Matrix

Voltage Frequency Part No.

220V
240V
208V

50Hz 30Z1233

voltage

specific

Input

common

input

220V
240V

60Hz 30Z1230

Transformer 30Z1230 shown for clarification

voltage
specific
Input

Page 34

APPENDIX 5: Hot air motor replacement procedure 1

we have improved the hot air motor assembly by enhancing the wave trap and balancing the
impeller which is now fitted by a grub screw to a flat on the shaft. The tolerances to manufacture
the motor shaft have also been tightened to improve the fit of the balanced impeller.

Parts required: 10C0192 service kit (consists of the following parts):

Part No. Description Quantity

11C0472 501Hot air motor service kit x1
40C1201 Hot air motor Wave Trap x1
2747048 Motor spacer board x1
101520 M4x10 Hex HD Screw x4
31Z4016 M5 flange nut x4
31Z5007 M5 steel spring washer x4
31Z5008 M5 steel washer large x4

Recommended tools:

RS Components Pt. No. 547-379 Quickset driver 1-6Nm with 0.1Nm increments
RS Components Pt. No. 769-002 1/4” hex to 1/4” square converter 50mm long

Procedure for fitting new RF trap and Motor assembly

Step 1 Isolate oven from mains supply.
Step 2 Remove necessary covers to obtain access to the rear of the oven.

Step 3 Remove shelf supports.
Step 4 Remove element cover plate.
Step 5 Remove and discard impellor. (Item 1)
Step 6 Disconnect motor at terminal block.

(note where each wire is connected)
Step 7 Remove and discard hot air motor assembly. (Item 2)
Step 8 Remove and discard motor screen tube with seal. (Item 3)

(check cavity surface and clean if necessary)

(Item 1)

(Item 3)

Parts to be removed

(Item 2)

Page 35

APPENDIX 5: Hot air motor replacement procedure 2

Step 9 Fit new wave trap Pt. No. 40C1201 to cavity. See figures 1(a) & 1(b)
(Making sure it is centred in the hole)

Ensure wave trap is fitted correctly and not caught around the edge of the hole.

See figure 2

Figure 1(a)

Rear of cavity

Pt. No. 101520

Figure 1(b)

Pt. No. 40C1201

Figure 2

Note: Ensure wave trap is fitted

correctly and not caught
around the edge of the hole.

Pt. No. 40C1201

Page 36

APPENDIX 5: Hot air motor replacement procedure 3

Step 10 Fit new hot air motor assembly Pt. No. 11C0472 (see diagrams below)

Make sure the motor shaft is centred in the hole

A) Fit motor assembly Pt. No. 11C0472 and secure finger tight with flange nuts &

washers.

B) Push the alignment tool (40C1211) onto the motor shaft and ensure initial step of the

tool locates into the wave trap. See figures 3a & 3b (see alignment tool figure 8)

C) Whilst supporting the weight of the motor assembly in one hand, tighten up the

securing nuts to 3.5Nm. This should align the shaft to the centre of the wave trap.
See figure 4

D) Remove the alignment tool and check shaft is centrally located. See figure 5

Note: Should the motor shaft not be central to the wave trap, follow the adjustment instructions

on the next page.

Figure 3a

Note:

Ensure
motor shaft
is centrally
located
through the
wave trap
hole.

Figure 5

Figure 3b

Figure 4

Earth point on

bottom left

mounting stud.

Page 37

APPENDIX 5: Hot air motor replacement procedure 4

Adjusting alignment procedure

To ensure correct alignment of the assembly there
are 2 procedures that may be required:

Procedure 1

The 4 bolts holding the wave trap to the cavity need
to be loosened off sufficiently to allow movement of
the wave trap.
See figure 6 (see Alignment tool figure 8)
You must then slide the alignment tool onto the
motor shaft, keeping pressure on the rear of the tool
only and not applying any sideways pressure. At the
same time pushing on the bolts of the wave trap to
manipulate the trap into a position where the outer
diameter of the tool goes into the hole of the wave
trap.Once the tool is located, tighten up the 4 bolts
and remove the alignment tool.

If procedure 1 is successful go to step 11

Procedure 2

With both wave trap and hot air motor secure, you
must then slide the alignment tool onto the motor
shaft, keeping pressure on the rear of the tool only
and not applying any sideways pressure until it
bottoms out on the cavity face. You must then push
sideways and forward on the tool to allo w the initial
step of the tool to go into the wave trap, making note
of which direction you had to push the tool for when
aligning the motor.
See figures 7(a) & 7(b) (see tool figure 8)
With the alignment tool in position, you must th en
loosen the 4 nuts holding the fibre board that the
motor is mounted to.This will allow you to push the
board not the motor in the same direction as they
pushed the tool. This will then bring the motor into
alignment with the wave trap.
Note: If you are looking into the cavity and had to
push the tool to the right, when looking at the motor

Figure 6

Loosen x4

Allows wave trap to
move to allow
alignment tool to fit.

Allows board to
be pushed to
allow alignment
tool to fit.

Figure 7a

Loosen x4

Alignment tool 40C1211

INITIAL STEP

Figure 8

PUSH

PUSH

Figure 7b

PUSH

PUSH

Page 38

APPENDIX 5: Hot air motor replacement procedure 5

Step 11 With the alignment correct Reconnect motor wires at terminal block. See figure 9a & 9b
Step 12 Fit new impeller to motor shaft. See figure 10a & 10b

(ensure grub screw lines up with the flat on the shaft)

Fit the screw to the impeller and wind down until you feel it touch the motor shaft. Then

gently push and pull the impeller back and forth to verify that the screw has located in the

Step 13 Refit element cover plate.
Step 14 Refit shelf su pp or ts.
Step 15 Test oven.

(Care should be taken when powering up ovens with covers removed)
(check motor is running freely and check emissions near new RF trap)

Step 16 Refit covers.

slot. Pull the screw to the front of the slot prior to securing.

Earth point on
bottom left
mounting stud

Figure 9a

Pull the screw

to the front of

the slot before

tightening the

screw down

push and pull

the impeller

back and forth

to verify that

the screw has

located in the

slot

Motor star t

Capacitor

6 uf

Hot air

motor

Live from PCB CN 7
Via gold resistor for
240v & 220V Ovens

Brown

Blue

Blue

Brown

Black

1 2 3

Figure 9b

Neutral from
Blower motor

Figure 10b Figure 10a

Page 39

APPENDIX 6: Temperature Sensor replacement

Mealstream ovens manufactured before March 2004

If you are required to fit a new temperature sensor to a Mealstream 501 oven on a service call,
you need to follow the procedure below to verify that the sensor is holding firm in the pocket.

The diagram below shows the area of the thermistor causing the problem. This problem has been
eliminated by increasing the hole depth in the temperature sensor pocket thus allowing the
thermistor to goes further into the pocket and lock into position.

Procedure for checking the temperature sensor fit in the sensor pocket

1. Fit the temperature sensor Pt. No. 50E123 as normal with a slight twist to lock the sensor into

the pocket.

2. If the sensor you have does not lock into the po cket and comes out of the pocket with little or

no effort, you will need to replace the pocket with one that has been modified as shown.

Part No. Description Quantity

11C0301 Temperature sensor pocket assembly 1
50E123 Thermistor 1

swaged area to lock onto

Old pocket

The temperature

sensor pocket has

been modified to

accommodate the

longer

temperature

sensor.

New pocket

16mm

swaged area to lock onto

24mm

Page 40

APPENDIX 7: Fuse change (FLM20) 1

Mealstream ovens manufactured before March 2004

Brief description:

13A anti-surge fuses Pt. No. 30Z0168 are no longer manufactured these are now replaced with
FLM020 fuses Pt. No. 30Z1177 for the Microwave circuit on all Mealstream 501 ovens.

To replace a fuse on an oven manufactured before March 2004 and fitted with this fuse type it is
necessary to replace the fuses and fuse holders with FLM 020 type.

Part No. Description Quantity

30Z1177 20A littlefuse FLM020 2
30Z1178 30A fuse holder (FLM Series) 2
31Z2092 Label - 20A FLM fuse 1
31Z3116 6x1/2” self tap pan 2

Procedure for replacing 13A anti-surge Fuses with FLM020 type

1. Isolate oven from mains power

supply.

2. Remove necessary covers to obtain

access to the L/H inner side panel.

3. Remove the wires from the existing fuse holders and fit them

to the FLM20 fuse holders Pt. No. 30Z1178. (A)

4. Remove fuses and unscrew the existing fuse holders, discard

all parts.

5. Secure the new fuse holders into positions using No.6x1/2” self

tap screw Pt. No. 31Z3116 x2. The fuse holders are to be
locked together prior to fitting into the hole shown in the
diagram. (B)

A

B

A

Page 1 of 2

Page 41

APPENDIX 7: Fuse change (FLM20) 2

6. Push fit the new fuses Pt. No. 30Z1177 into the fuse holders.

7. Fit new label Pt. No. 31Z2092 over the existing label leaving the F5 and F1 still showing (C)

8. Power up the oven and check machine functions correctly.

(Care should be taken when powering up ovens with covers removed).

If fuse still blows, check microswitch setup is correct and replace if necessary.

9. Turn off the power and isolate the oven from the mains power supply.

10. Replace covers.

20A FUSE

FLM SERIES

MERRYCHEF PART

No. 30Z1177

C

Page 42

APPENDIX 8: Tim Hortons Ovens 1

This appendix list the parts and procedures for Tim Hortons Mealstream 501 models
which are a vend type oven pre-programmed from a MenuKey.

In order to carry out the Power Test on Tim Hortons variant Ovens, the Icon Pad
programs on the control panel need to be switched to Engineering Program Mode.
Engineering Mode does not affect the current Menukey program settings for the Icon
pads and the current Menukey programs are automatically restored when the oven is
next switched on.

To switch to Engine e ring Mode Program s :

1 With the oven switched off hold down the CANCEL Pad and switch the oven ON, the disp lay

shows the current Menukey Code, continue to hold the CANCEL Pad for approximately 10
seconds until the display shows

2 Programs will be set as follows:

Program Number Time Temp Power

EE 00:00 indicating the oven is now in engineering mode

Pad 01 1 minute 3 secs Off 100%
Pad 02 3 minutes Off 100%
Pad 03

Pad 04

All other programs will be blank

3 Follow the Power test procedure as detailed on Page 24 using Program Pad 01 ( Cake) to

give the required 1 minute 3 seconds at 100% Microwave Power setting.

4 On completion the current Menukey programs are automatically restored when the oven is

next switched on.

Stage 1 30 minutes 480 °F 100%

Stage 2

59 minutes 59secs 480 °F None

29 minutes 59 secs 480 °F 50%

Page 43

APPENDIX 8: Tim Hortons Ovens 2

PROCEDURE FOR POWER OUTPUT MEASUREMENT

The power output specification, 1425W on this model is established under IEC 705 standard
method. This method is only workable in Laboratory controlled conditions.

An approximate method is as follows:

To carry out this test the Icon Pads need to be switched to ENGINEERING MODE PROGRAMS
See previous page

1 Fill one beaker ( glass or plastic ) with one litre ( 1.78 pints ) of tap water

( at about 20ºC/68ºF ) and measure the water temperature.
( Use a thermometer with a

2 Place the beaker in the centre of the cavity.

3

Tim Hortons Ovens only

With the oven in ENGINEERING MODE Press Pad 01 (Cake) and any Load Pad ( Quarter,
Half, Full ) Wait until the counter reaches zero.

4 Take the beaker out immediately stir the water with a plastic implement and measure the

water temperature.

5 Calculate the temperature rise of water in the beaker. The temperature rise of the water

should be within the following range:
Temperature Rise

15ºC ( 27ºF ) Minimum
20ºC ( 36ºF ) Maximum

Note:
Power Output is affected by the line voltage under load. For correct Power Output
measurement, the line voltage under load must be correct.

1

/10, 0.1 degree gauge ).

Page 44

APPENDIX 8: Tim Hortons Ovens 3

Door and cavity roof:

2

8

2

1

4

6

7

5

No Description Part No.

1 Stirrer glass assy. ( inc. long seals ) 11C0319
2 Cavity roof seal (short) 790052
3 Door Handle T owel Rail 32Z1064
4 Bolt 1/4" 20 UNC 3/4" Hex 109050
5 Door Handle 40C1020
6 Spring Washer 31Z5005
7 Flat Washer S/S M6 x 20 104054
8 Door Assembly Tim Hortons 11C0380

3

Page 45

APPENDIX 8: Tim Hortons Ovens 4

Tim Horton special parts:

16

15

14

12

13

Tim Hortons

No Description Part No.

12 Wire Rack 40C1011
13 Crumb Tray RBR290X02
14 Shelf Support

Tim Hortons
15 Shelf support fixing bolt 80T7133
16 Push fit bumper ( Rear Panel ) 31Z1187

10C0174

Page 46

APPENDIX 8: Tim Hortons Ovens 5

Tim Hortons control panel

K

L

For 240V model

No Description Part No.

30 Control Panel Assy with Menukey 11C0414
31 Logic Board 11C0411
32 Relay Board 11C0403

M

Preheat

K

Cancel

L

Icon Cook Pads

M

MenuKey™

N

Quarter, Half

O

& Full Batch Load

M

O

N

MENU

KEY

Mealstream 501 US Tim Hortons & Unbranded Variant

Note:PINS 1-4 Lower Layer & Pins 5-10 upper layer

Page 47

APPENDIX 9:
PROCEDURE FOR DOOR INTERLOCK ADJUSTMENT AND TEST (1)

The door on the Mealstream oven is monitored by three microswitches. These are used in the
conventional “Primary, Secondary and Monitor” switch arrangement shown below.
The switches operate as follows:

Door Interlock Arrangement

Switches shown in Door Closed position

L1

Power In

L2

1. Monitor switch ( 14 ,Top left-hand Side ). The Monitor switch will produce
a short circuit across the mains supply if the Primary interlock switch is
faulty, when the door is opened, thus blowing the microwave fuse and
rendering the oven inoperative.

2. Primary Interlock ( 11 , Bottom left-hand ) and Secondary Interlock
( 17 , Bottom right-hand ) Switches. Operate simultaneously.
The Primary switch will cut off the microwave emissions from the oven when
the door is opened by breaking the electrical supply circuit to the
transformers. The Secondary interlock switch will cut off the microwave
emission if the Primary switch have failed.

Note:

If operation of the Monitor switch has caused the Microwave Fuse to blow,
the Primary and Monitor microswitches must be changed, as they may have
been damaged by the high short-circuit currents involved.

11 Primary switch

17 Secondary switch

Power Out

14 Monitor switch

Page 48

PROCEDURE FOR DOOR INTERLOCK ADJUSTMENT AND TEST (2)

Please Note

DO NOT attempt to carry out the following procedure

unless you have the following tools and parts.

Continuity Meter

Door Spacer Kit
Part No. 10C0171

Spacer No. required Part No.

S10 Door Spacer 10mm
S5 Door Spacer 5mm
S1 Door Spacer 1mm

2 40C1119
2 40C1118
2 40C1114

WARNING

Before starting this test procedure please make sure that the oven is disconnected
from the electrical supply and that the oven power switch (ON/OFF) is in the OFF
position.

After each step check that the interlocks are operating in the correct order using a
continuity meter.

See Safety Code ( Page 3 )

Disconnect the microswitches and check for the continuity of the switches with a continuity meter

Step 1: Set the interlock so that they activate in the following order.

When closing the door.

Interlock Order
SW1 (Monitor) 1st
SW2 (Primary) 2
SW3 (Secondary) 2

When opening the door.

Interlock Order
SW1 (Monitor) 3rd
SW2 (Primary) 1
SW3 (Secondary) 1

nd

Note both SW2 and SW3 activate together

nd

Note both SW2 and SW3 activate together

st

Note both SW2 and SW3 activate together

st

Note both SW2 and SW3 activate together

Page 49

PROCEDURE FOR DOOR INTERLOCK ADJUSTMENT AND TEST (3)

Step 2: Insert S10 10mm spacer into door.

(See figure 1 below for inserting spacer
correctly).

Step 3: Remove S10 10mm spacer and insert S1 1mm

spacer into the door and close the door.

Step 4: Remove S1 1mm spacer and insert S5 5mm

spacer into the door and close the door.

If an oven fails this sequence

then check the microswitches are functioning

Interlock Order

SW1 (Monitor) CLOSED
SW2 (Primary) OPEN
SW3 (Secondary) OPEN

Interlock Order
SW1 (Monitor) OPEN
SW2 (Primary) CLOSED
SW3 (Secondary) CLOSED

Interlock Order
SW1 (Monitor) OPEN
SW2 (Primary) OPEN
SW3 (Secondary) OPEN

correctly and repeat steps 1 to 4.

After carrying out this procedure make sure that the interlock monitor switch is properly connected

according to the circuit diagram on pages 44-46.

Figure 1

Door side seal

Door top seal

Door spacer

The door spacer must always be
located on the point where the side
seals and top seals meet.

Please note.

It is very important after completing this procedure to carry out a

microwave emissions test procedure. See pages 51-52.

Page 50

PROCEDURE FOR MICROWAVE EMISSIONS TEST (1)

Warning

Check for radiation leakage after servicing. Should the leakage be more than 4mW/cm² Inform
Merrychef service centre immediately. After repa iring or replacing any radiation safety device,
keep a written record for future reference this requirement must be strictly observed. In addition,
the leakage reading must be recorded on the service repair documentation while in the
customer’s premises.

Please Note

DO NOT attempt to carry out the following procedure

unless you have the following tools.

Tools required for microwave leakage test

Tim Hortons

600ml glass beaker
Supply of cold water
Microwave leakage meter

To carry out this test the Icon Pads

need to be switched to

ENGINEERING MODE PROGRAMS

See Appendix 8

Read and understand all of these notes and procedure before carrying out this operation.
Note before measuring.

• Make sure that the survey meter you are using has been calibrated and is suitable for
measuring frequencies of 2,450 MHz.

• Do not exceed meter full scale deflection, leakage meter should initially be set to the
highest scale, then adjusted down as necessary to ensure that low readings are measured
on the most sensitive range.

• To prevent false readings, hold the probe on the grip provided and move along the areas
indicated on the following page. The probe should be moved at 2.5cm/second.

• With any casework removed the leakage should not exceed 4mW/cm².

• When measuring the leakage, always hold the probe at 50mm from the test area using the

probe supplied with the instrum en t.

• Always hold the probe at right angles to the oven and point of measurement.

Procedure

1 Place 275ml of cold water in the 600ml glass beaker.
2 Place the 600ml glass beaker in the centre of oven.
3 Close the door and set time for 30 seconds then press Power pad 100%

(change water every 30 seconds to prevent boiling).
Tim Hortons: In ENGINEERING MODE (see Appendix 8 ) press Pad 01 then any Load pad
(QUARTER, HALF, FULL) watch time display and open door at 30 seconds.

4 Set the leakage meter to the appropriate scale/range.
5 Move the survey meter probe along the areas indicated in (Figures 1 to 4 page 52).
6 Remember to change the water after 30 seconds since water that boils will result in

inaccurate readings.

Page 51

PROCEDURE FOR MICROWAVE EMISSIONS TEST (2)

• Readings must be below 4mW/cm². If a level greater that 4mW/cm² is observed,

this should be reported to Merrychef Service Department immediately.

• In any case, notes should be kept of the leakage that is observed. In terms of level and
position on the oven. This should be kept with the service documentation.

Control Panel - Figure 2
Door Perimeter - Figure 2
Rear and Side Covers - Figure 1, 3 & 4
Left & right Side Air Filters. - Figure 3 & 4

Test for microwave leakage at all points marked with a

Fig. 1

Fig. 3

Fig. 2

Fig. 4

Page 52

Manual corrections and modifications

Whilst every effort has been made to ensure that the information contained in this manual is
accurate and complete, if you believe that an error has been made, or if you have any
suggestions for how the manual could be improved, please fill in and return this form . A review of
any forms returned will be made on a regular basis, and the manual will be updated if required.

Name

Address

Page on which error occurs (if applicable) - Mealstream 500 Series

Description of error

Suggestion for improvement to manual

Please return this form to:

Service Dept.
Merrychef Limited,

Station Road West,
Ash Vale, Aldershot
Hampshire GU12 5XA
United Kingdom
Tel: [phone] Fax: [phone]
Internet address: http://www.merrychef.com
E-mail: [e-mail]

Page 34 Mealstream Ovens 32Z3387 Issue 3