S E R V I C E M A N U A L For all MC-Series models manufactured from January 2001 Part No. 32Z3329e Issue No.
Table of Contents Safety Code...........................................................................3 Product Specifications MC Series .........................................4 Installation Instructions ..........................................................5 Error Codes and Diagnostics.................................................6 A - Power Output Testing to BS EN 60335-2-25:1996 ..........7 B - Power Output Testing ......................................................
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 for the Merrychef MC Series Commercial 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.
PRODUCT SPECIFICATIONS Model No. MC-Seies Model No. + Voltage + Frequency + Country Model Number Specification: Voltage 2 = 220-230V a.c. 4= 230-240V a.c. Frequency 5 = 50 Hz 6= 60 Hz Country UK = EX = Export United Kingdom Power Requirements MC1000C45UK MC1000C25EX MC1400C45UK MC1400C25EX MC1800C45UK MC1800C25EX 230-240V ac 50 Hz 13.0A Single Phase 2 Wire + Earth 220-230V ac 50 Hz 14.2A Single Phase 2 Wire + Earth 230-240V ac 50 Hz 13.0A Single Phase 2 Wire + Earth 220-230V ac 50 Hz 14.
INSTALLATION INSTRUCTIONS MC Series Ovens Power Supply Requirements The MC–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 16A.
Error Codes and Diagnostics The MC–Series oven will identify some of the most common problems by flashing an error message code in the time display window. These are the error messages, and suggestions for repairing them. MC Series Ovens 32Z3329 Issue 4 1 Door not fully shut. Close door fully. 2 Possible electrical fault Door switch inoperative. 1 No time has been set. Set a time. 2 Invalid time has been set. Set a valid time. 3 Invalid program has been Use call-back set. program.
Procedure A - Power Output Test in accordance with BS EN 60335-2-25:1996 Annex AA This test is given in the BSI test standard for microwave ovens. It is reproduced below - 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.
Procedure B - Simplified Power 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 2 3 4 5 6 7 8 Measure 1 litre of cold water into the tray using the measuring jug. Measure the water temperature, and record it as T[s]. Place the tray in the oven and close the door. Turn the oven on. Set the timer to 1:02. Press the “100%” pad.
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. 1 Isolate the oven from the mains supply. 2 Ensure that the High Voltage Capacitor is discharged before commencing work. 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 .
DOOR INTERLOCK OPERATION Door Interlock Operation The door on the oven is monitored by four microswitches. Three of these are used in the conventional “Primary, Secondary and Monitor” switch arrangement shown below, while the fourth is a low-voltage switch linked directly to the control circuitry. MC– Series Door Interlock Arrangement 66d L 66a Power In 66c 6 6 Power Out N The switches operate as follows: 1. Monitor Switch [66b , Top ]. As the door is closed, the monitor switch is opened. 2.
Exploded View – MC Series Note: Model MC1000 has only one Magnetron assembly parts 51, 61 MC Series Ovens 32Z3329 Issue 4 Page 11
Door Assembly MC Series Ovens 32Z3329 Issue 4 Page 12
Door Replacement and Door Adjustment DOOR REPLACEMENT 1. 2. 3. Remove four screws holding the Upper and Lower Hinge Plate [14] to the oven cavity. Remove Door Assembly [80] by pulling it forward. On re-installing new door assembly, secure the upper and lower oven hinges with the four mounting screws to the oven cavity. Make sure the door is parallel with the bottom line of the oven cavity face and the catches pass through the catch holes correctly.
Door Servicing CHOKE COVER REMOVAL 1. Insert a flat type screw driver into the gap between the Choke Cover [16] and Door Body [7] as shown below to free the engaging clips. A protective piece of tape should be used so as not to damage the door panel. 2. Lift up the Choke Cover. DOOR COMPONENTS REMOVAL Place the Door Assembly [80] on a soft cloth with the Choke Cover [16] facing up. UPPER AND LOWER OVEN HINGE REMOVAL 1. Remove the Choke Cover, referring to "CHOKE COVER REMOVAL". 2.
Door Interlock Details MC Series Ovens 32Z3329 Issue 4 Page 15
Membrane Panel Circuit You will need: A Digital Multi-meter (D.M.M.) Procedure: 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 Assembly. 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, reassemble and re-test the control housing.
INPUT WIRING DETAILS MC Series Ovens 32Z3329 Issue 4 Page 17
Part Number Identification Chart: MC series ovens No Description MC1000 MC1400 MC1800 Part No. Part No. Part No.
Part Number Identification Chart: MC series ovens No Description MC1000 MC1400 MC1800 Part No Part No Part No 46 Rear Air Guide 30M0046 30M0046 30M0046 47 Upper Air Duct 30M0047 30M0047 30M0047 48 Cooling Fan Assembly 30M0048 30M0048 30M0048 49 Gold Resistor 30Z0283 30Z0283 30Z0283 51 Magnetron Thermostat 30M0051 30M0051 30M0051 52 10A Fuse In-line Assembly 11M0330 11M0330 11M0330 56 Fan Scroll 30M0056 30M0056 30M0056 57 Main Capacitor Bracket 30M0057 30M0057 3
CIRCUIT DIAGRAM: MC Series ovens MC Series Ovens 32Z3329 Issue 4 Page 20
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.
