Merloni L55 NF LCD, Technical Manual

Page 1: ... FREEZERS All parts included in this document are the property of Merloni Elettrodomestici S p A All rights reserved This document and the information it contains are supplied without liability arising from errors or omissions No part may be reproduced used or copied without written consent or a con tractual clause ...

Page 2: ...aporator Fan No Frost only 13 7 Condenser fan 14 8 Thermo fuse No Frost only 15 6 ANALYSIS OF PROBES 16 7 ANALYSIS OF MEMORY 18 8 ANALYSIS OF BUZZER 19 9 ANALYSIS OF LCD DISPLAY 20 10 ANALYSIS OF SERIAL LINES 21 11 DEMO MODE FUNCTION 22 VE ELECTRICAL DIAGRAM 23 VE SCHEMATIC DIAGRAM 24 NF ELECTRICAL DIAGRAM 25 NF SCHEMATIC DIAGRAM 26 ELECTRONIC BOARD 27 CHARACTERISTICS OF R600 28 MAIN DIFFERENCES B...

Page 3: ...FAN in fridge comp 1 CONDENSER FAN not run by boards 1 COMPRESSOR 1 SOLENOID VALVE 1 FR LAMP 1 AMBIENT FAN in fridge comp 2 DEFROST ELEMENTS evap and drip tray 1 NF FZ FAN in freezer comp 1 CONDENSER FAN not run by boards 1 THERMOFUSE not run by boards Input 2 KNOBS 2 BUTTONS 1 FR PROBE in fridge comp 1 FR EV PROBE in contact with FR evaporator 1 FZ AMBIENT PROBE in freezer comp 1 FR DOOR SWITCH t...

Page 4: ...AR RATING REFRIGERATION TYPE SPECIAL PERFORMANCE ENERGY CLASS GAS DOOR OPENING MARKET B Bult in C Combi D Double door O One Door T Under Table F Freezer P Decor panelable A Load bearing X Cabinet Blank Built in S Self Ventilated Blank Nothing 2 numbers 1 Style 2 Ecotech 3 Class Blank Combi Blank Double door o 4 One Door 0 4 Under Table Blank Freezer Blank Static V Ventilated N No Frost G Global Ai...

Page 5: ...ively to the Freezer compartment Their function is to alert the user to the storage condition of food An A1 alarm signal is triggered when the freezer temperature is higher than 2 C the freezer temperature stops for more than 4 hours between 6 C and 2 C An A2 alarm signal is triggered when the freezer temperature is higher than 8 C an A1 alarm signal has been ongoing for over 24 hours ...

Page 6: ...bes active after approx 10sec fridge ambient fan fault Super Cool function symbol starts flashing freezer ambient fan fault the Super Freeze function symbol starts flashing fridge evaporator probe fault Holiday function symbol starts flashing EEPROM Buzzer sounds if KO Appliance OFF freezer knob to zero 4 min after activation Fridge lamp Visual check by operator the fridge lamp stays on approx 15s...

Page 7: ...minute delayed start Possible cause of malfunction Microcontroller management Compressor driver circuit on the board Connection on the board Wiring Connection on the compressor Internal compressor breakdown fault TESTING General on the appliance force the compressor to switch on by activating the 24h SUPER FREEZE function and check that the compressor switches on Remember the 8 minutes of compress...

Page 8: ...r circuit on the board Connection on the board Wiring Connections on the lamp Connections on fridge door switch Lamp Fridge door switch TESTING General on the appliance switch on the appliance open the door and verify that the lamp switches on carry out the check using the Autotest procedure Wiring check for continuity and short circuits check the connections connectors and terminals check for pre...

Page 9: ...to force the solenoid valve into the desired state The pur pose of this is to move the internal stop and thus ensure during the exchange the re moval of any impurities To ensure that no interference has altered the state of the solenoid valve which is sen sitive to electrical interference and that it is in the desired condition it is automatically refreshed every 15 minutes The fridge nonetheless ...

Page 10: ...mestici 55 CM WIDE BUILT IN FRIDGE FREEZERS Technical Manual I 04 10 22 01 10 33 Language Issue Edition Page Tirac not permitted Tirac in conduction 3 3 ms 20 msec 50 Hz Driver signal EV 10 impulses Mains supply signal ...

Page 11: ...n Ambient fan TESTING General on the appliance direct cold air into both fridge and freezer compartments open the door and hold down the fridge door switch Visually check that after the de layed activation period has elapsed the ambient fan starts working Carry out the check using the Autotest procedure Wiring check for continuity and short circuits check the connections connectors and terminals c...

Page 12: ...anagement Resistor driver circuit on the board Connection on the board Wiring Connection on the elements Elements Blown thermo fuse TESTING General on the appliance Carry out the check using the Autotest procedure Wiring check for continuity and short circuits check the connections connectors and terminals check for presence of voltage check that the thermo fuse is not open Component check with si...

Page 13: ...rator has cooled to be low 18 C in the first cycle after a defrosting POSSIBLE CAUSE OF MALFUNCTION Microcontroller management FZ evaporator fan driver circuit on the board Connection on the board Wiring Connection on the FZ evaporator fan FZ evaporator fan TESTING General on the appliance Carry out the check using the Autotest procedure Wiring check for continuity and short circuits check the con...

Page 14: ...e board Connection on the compressor terminal board Wiring Connection on the condenser fan Condenser fan TESTING General on the appliance force the compressor to switch on and as a result the fan by activating the 24h SUPER FREEZE function and verify that the fan switches on at the same time as the compressor Remember the 8 minutes of compressor protection Wiring check for continuity and short cir...

Page 15: ...used on the metal support in contact with the freezer evaporator This component having been tripped due to excessive temperature can no longer be used POSSIBLE CAUSE OF MALFUNCTION Connection on thermo fuse Wiring Thermo fuse TESTING General on the appliance carry out the check using the Autotest procedure and check for correct functioning of the defrosting resistors a malfunction could in any cas...

Page 16: ...data to regulate the refrigerator s thermostat This is therefore the most important probe in terms of refrigerator operation since it determines the thermal cycles activating and deactivating the compressor and solenoid valve REFRIGERATOR EVAPORATOR PROBE This probe is located on the fridge evaporator in the same area as the thermostat bulb in the electromechanical version Its task is to measure t...

Page 17: ...touching it with your hand where possi ble and check the variation in the resistive value Board visual check and quick check of the board blowouts or burnouts etc check by using a replacement Temp C Ohm Resistor Temp C Ohm R esistor Temp C Ohm Resistor 50 973 6 2 9701 22 29045 45 1181 3 10215 23 30797 40 1493 4 10759 24 32668 35 1765 5 11337 25 34666 30 2176 6 11949 26 36800 25 1700 7 12598 27 390...

Page 18: ...tion between the micro and the memory on a special 8 pin socket on the Power board can have a strong bearing on the functioning of the appliance and on the user s adjustments POSSIBLE CAUSE OF MALFUNCTION Microcontroller management Memory circuit on the board Memory TESTING General on the appliance Carry out the check using the Autotest procedure Board visual check and quick check of the board blo...

Page 19: ...UNCTION Microcontroller management Driver circuit on the board Buzzer TESTING General on the appliance and component starting from the appliance ON condi tion keep the refrigerator and or the freezer door open for more than three to four minutes so as to force the door open alarm condition check that the buzzer starts to sound and turns off just by the door being closed failure to activate could a...

Page 20: ...rtment POSSIBLE CAUSE OF MALFUNCTION Microprocessor management Driver circuit on the board Display TESTING General on the appliance and component switch on the appliance and turn the two knobs and press the buttons to change the settings Wiring between the two boards check for continuity and short circuits check the connections connectors and terminals Board visual check and quick check of the Dis...

Page 21: ... etc by means of special HW and SW POSSIBLE CAUSE OF MALFUNCTION Microprocessor management Input Output circuit on the board Connection on the board Wiring Connection in the compressor bay TESTING General on the appliance the serial line can only be verified by means of connection to a PC Wiring check for continuity and short circuits check the connections connectors and terminals check for foam o...

Page 22: ...letely accessible without controlling any load compressor fridge fan and solenoid valve ir respective of the status of the appliance The lamp status is controlled according to re frigerator door opening DEMO MODE activated is shown by the flashing with the message OFF in both fridge and freezer compartments The DEMO MODE can be deactivated by holding the SELECT RESET and MODE keys at the same time...

Page 23: ...OMPARTMENT FAN UNIT COMPRESSOR BAY FAN UNIT COMPRESSOR UNIT FRIDGE LAMP BUTTON FRIDGE LAMP STARTER DEVICE THERMOPROTECTOR BOARD AND DRAIN SUPPLY SERIAL PROBES FRIDGE DOOR BUTTON TEMPERATURE PROBES We reserve the property rights for this technical drawing which may not be used or reproduced Dimensions do not take treatment into account SERIAL SERIAL SERIAL SERIAL FREEZER AMBIENT PROBE FRIDGE AMBIEN...

Page 24: ... I 04 10 22 01 24 33 Language Issue Edition Page VE SCHEMATIC DIAGRAM WIRES WITH DIFFERENT SECTION FR DOOR SWITCH FRIDGE FAN 6 WAY EDGE CONNECTOR BLUE 4 BROWN 1 WHITE BROWN 2 WHITE BLACK RED BLUE 3 BLUE 1 BLUE BROWN SERIAL FRIDGE EVAP FRIDGE FAN FREEZER FAN COMPR COND CONDENSER ...

Page 25: ...MV3 CO ILI LI PTC RH TF RES EVAP RES GOCC CN1 CN2 CN3 CN4 LINE NEUTRAL SOLENOID VALVE FRIDGE COMPARTMENT FAN UNIT FREEZER COMPARTMENT FAN UNIT COMPRESSOR BAY FAN UNIT COMPRESSOR UNIT FRIDGE LAMP BUTTON FRIDGE LAMP STARTER DEVICE THERMOPROTECTOR THERMO FUSE EVAPORATOR ELEMENT DRIP TRAY ELEMENT BOARD AND DRAIN SUPPLY SERIAL PROBES FRIDGE DOOR BUTTON We reserve the property rights for this technical ...

Page 26: ...ion Page NF SCHEMATIC DIAGRAM FR DOOR SWITCH FRIDGE FAN 6 WAY EDGE CONNECTOR BLUE 9 BROWN 3 BLACK 2 BROWN 2 YELLOW BLACK 1 RED 1 BLUE 7 BLUE 3 YELLOW 1 GREY SERIAL FRIDGE EVAP FRIDGE FAN FREEZER FAN COMPR COND CONDENS FREEZER EVAP INDICATIVE WHITE BROWN 1 THERMO FUSE DRIP TRAY RESISTOR EVAPORATOR RESISTOR FREEZER FAN ...

Page 27: ...T IN FRIDGE FREEZERS Technical Manual I 04 10 22 01 27 33 Language Issue Edition Page ELECTRONIC BOARD Triac Load activated Q2 Freezer fan Q10 Fridge lamp Q11 Solenoid valve Q9 Defrost elements Q8 Fridge fan Q8 Q10 Q2 Q9 Q11 Compressor relay ...

Page 28: ...SADVANTAGES Greater attention to charges a few grams less more can cause significant charge imbalances Greater attention to evacuation lower working pressures greater attention to air infiltration due to the low pres sures reached Greater problems of gas flow noise in the circuit MAIN DIFFERENCES BETWEEN R134 AND R600 R134 R600 Sensitivity to humidity High synthetic oil Negligible mineral oil Nois...

Page 29: ...TURES OF CIRCUIT IN C Component Temperature Filter condensation Tamb 10 15 C Evaporator 30 C or lower with thermocouple on metal tube 24 26 thermocouple on plastic cell Return tube Tamb Temperature measured on tube as far as possible from the compressor 1 COMPRESSOR 2 ANTI CONDENSATION TUBE 3 CONDENSER 4 MOLECULAR FILTER 5 CAPILLARY TUBE 6 FREEZER EVAPORATOR 7 FRIDGE EVAPORATOR ...

Page 30: ...on pressure corresponding to 28 C 30 C Refrigerator plate completely frosted over so that T1 T2 thermocouple position as shown in the figure Filter temperature and corresponding condensation pressure delivered to compressor so that T Tambient 10 15 C E g Tamb 25 C 35 T filter 40 Depending on the type of refrigerant and application Temperature on plastic cell 24 26 C ...

Page 31: ...t temperature Notes With fan condensers it is advisable to insulate the thermocouple on the filter using armaflex or similar materials position the thermocouple using adhesive tape possibly metallic protect the thermocouple with armaflex Exposure limit Yes Irritant No Sensitizing No Carcinogenic No Health 0 Inflammability 4 Instability 0 0 no risk 1 low risk 2 moderate risk 3 high risk 4 very high...

Page 32: ...ronic management 1 COMPRESSOR 2 CONDENSER 3 ANTI CONDENSATION TUBE LIGHT BLUE 4 RETURN TUBE GREEN 5 FRIDGE CAPILLARY TUBE RED 6 FREEZER CAPILLARY TUBE YELLOW 7 FREEZER EVAPORATOR RED 8 FRIDGE EVAPORATOR RED 9 SOLENOID VALVE 10 ACCUMULATED GAS CANISTER 11 MOLECULAR FILTER EVAPORATOR COMPONENTS Low Pressure RED Fridge Freezer YELLOW Fridge Freezer GREEN Fridge Freezer COMMON COMPONENTS High Pressure...

Page 33: ...oni Elettrodomestici I 04 10 22 01 33 33 Language Issue Edition Page Merloni Elettrodomestici S p A 47 Viale Aristide Merloni Fabriano 60044 Italy tel 0732 6611 telex 560196 fax 0732 662954 www Merloni com ...