Panasonic NR-B37MV2 User manual

Order No. PHAT070202S3
(Revision : Jul. 2011)
Service Manual
Refrigerator
NR-B37MV2
NR-B41MV2
Product Colour
Silver (SL)
Destination
Thailand
© Panasonic Home Appliances (Thailand) Co., Ltd. 2007.
All rights reserved. Unauthorized copying and distribution
is a violation of law.
There are special components used in this equipment which are important for safety. These parts are marked by
in the Schematic Diagrams, Circuit Board Diagrams, Exploded Views and Replacement Parts List. It is essential that
these critical parts should be replaced with manufacturer’s specified parts to prevent shock, fire or other hazards. Do
not modify the original design without permission of manufacturer.
IMPORTANT SAFETY NOTICE
WARNING
The service information is designed for experienced repair technicians only and is not designed for use by the general
public. It does not contain warnings or cautions to advise non-technical individuals of potential dangers in attempting
to service a product. Products powered by electricity should be serviced or repaired only by experienced professional
technicians. Any attempt to service or repair the product or products dealt within this service information by anyone
else could result in serious injury or death.
CFCs have been used in refrigerant as refrigerator and the insulation materials for many years. But it
is now known that these compounds which once seemed so ideal for use as cleaning agents and in
refrigeration systems, destroy the earth’s ozone layer as a result, an international body decided on a
total worldwide ban of harmful CFCs by the end of 1995.

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CONTENT
Page
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
1. Safety Cautions for Repairing
1.1 Warning
1.2 Caution
2. Specification and Components
3. Performance Data
3.1 NR-B37MV2
3.2 NR-B41MV2
4. Self Protecting Function
4.1 Protecting for IC
4.2 Protection for compressor locked
4.3 Protection for power supply droping
5. Self Diagnoising Function
6. Temperature Control
7. Refrigerator Instruction Guideline
8. Troubleshooting Guide
8.1 Not cool at all [ Both PC & FC (compressor does not operate) ]
8.2 Cool, not enough [ Both PC & FC (compressor operates) ]
9. Schematic Diagram
9.1 Wiring Connection Diagram
10. Parts Exploded View and Replacement Parts List
10.1 Part Exploded View : Body
10.2 Part Exploded View : Door
10.3 Part Exploded View : Packing
10.4 Replacement Parts List : NR-B37MV2, NR-B41MV2
11. Detail Change Notice
NR-B37MV2 / NR-B41MV2

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1. SAFETY CAUTIONS FOR REPAIRING
When you repair the refrigerator, please kindly take care for the following cautions.
1.1 Warning
Before repairing unit, unplug supply cord
• Before you repair the refrigerator, please unplug the supply cord.
Use authentic parts when repairing
• When you replace the parts, please use authentic parts to replace defective parts.
Caution during brazing
• When you use touch for brazing, please ensure ventilation.
Otherwise, you will be poisoned by carbon monoxide.
Pay attention to using refrigerant
• If refrigerant touches fire, the gas becomes poisonous gas.
Pay attention to getting electricity shock
• When you check the voltage of terminal, please do not touch the electricity part terminal.
• When you replace the parts, please wait for 3 minutes at least for discharging capacitor.
Check safety after repairing
• Check the screws, parts, lead wires to take in place.
• Check the repairing portion whether circumferential parts are damaged or not.
• Check insulation resistance between supply plug and earth.
• When install refrigerator, check condition of supply cord and plug.
• Wipe off the dust on plug.
• Cutting and seal the electric device carefully.
1.2 Caution
Watch the hot parts
• During operation and after operation, compressor and pipes are hot.
• Also, under these condition, heater are hot.
• Do not burn your fingers when you touch it.
Pay attention to refrigerant
• Do not touch liquid refrigerant. Otherwise your hands may be burnt.
Pay attention to edge of parts
• Otherwise, your fingers may be cut.
Pay attention to fins of evaporator and condenser
• Otherwise, your fingers may be cut.
Before transportatin, adjust the bolt
• Otherwise, the floor may be damaged.
Do not touch the pipe after brazing
• Otherwise, your hands may be burnt.
NR-B37MV2 / NR-B41MV2

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2. SPECIFICATION AND COMPONENTS
Destination
Model
Plug
Power Source
Specification
Thailand
NR-B37MV2 / NR-B41MV2
C2P
220V AC 50Hz
Capacity
External
Dimensions
Width (mm)
Depth (mm)
Height (mm)
Net Weight (Kgs.)
Temperature Control
Defrosting
Freezer Star Rating
Exterior Finish (cabinet / door)
Inner Liner
Insulation
355L / 395L
(FC :102, PC : 253 / 293)
675
695
1629 / 1769
69 / 72 Kgs.
FC : Electronic control (PCB)
PC : Baffle damper thermostat
Full-automatic heater deater defrost with a timer
Full-automatic heater (Forcibly evaporated into the air)
PCM color / PCM color - (Polyester paint coating / Polyester paint steel)
Vacuum fomed ABS resin
Polyurethane foam (cabinet / door)
Electric Parts
PC Heater
Door Switch
Fan Motor
Fan Blade
Type
Rating
Lamp Bulb
PTC Relay
Defrost Timer
Defrost Heater
Motor Protector
Running Capacitor
Defrost Sensor
(DFC)
Type
Rating
FC Sensor
(FCC)
Temperature Fuse
Resistance wire vinyl covered heater 3.14W / 220, 3.22W/M, 15421 ohms
D3D - 121
250V / 0.5A
DC 14V / 1.54W
Ø 90mm. prop fan (Box Type)
E14 / 22, 240V / 15W
PTH7M330MD2
Radiant heater MM6 - 4343 220V / 183W
MM3 - 20DCW
4µF - 400V
PTC
10
B = 3819K ± 2%
R = 3.899KΩ± 3%
PTC
-30
B = 3850K ± 2%
R = 18.9KΩ± 1.8%
250V / 10A / 73°C
PAS-B37MV2 / B41MV2 (Control Board)TYPE
Electronic PCB Control
(1) Ambient Temp. over 34°C 7h ADD
(2) Ambient Temp. 28°C ~ 33°C 7h ADD
(3) Ambient Temp. 11°C ~ 27°C 7h ADD
(4) Ambient Temp. cover 10°C 13h ADD
(5) Power ON 4h ADD
Sealed Unit
Compressor
(Winding Resistance at 20
°C
Evaporator
Condenser
Refrigerant Type
Charge
Oil Charge
ETI57C13DCH-C0ECS
Fin tube type
Wrapper type (concealed condenser)
HFC - 134a 130 gm
130 gm
215ml 9 (Freol ∝ ~ 10)
NR-B37MV2 / NR-B41MV2

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3. PERFORMANCE DATA
3.1 NR-B37MV2
Thermostat Dial Setting
Mean Fresh Food Compartment Temperature t3 (°C)
(°C)
(°C)
(°C)
(°C)
(°C)
(kWh/Day)
Mean Freezer Load Temperature
Vegetable Crisper Temperature
PC Door Shelf Upper Temperature
Egg Tray Temperature
PC Door Shelf Bottom Temperature
Power Consumption
(%)Running Ratio
“ 3 ” “ 2 ” “ 1 ”
1.0 ± 2.5 3.5 ± 2.5 6.5 ± 2.5
-21.5 ± 2.5 -19.5 ± 2.5 -15.0 ± 2.5
- 4.5 ± 2.5 -
- 6.0 ± 2.5 -
- 8.0 ± 2.5 -
- 5.0 ± 2.5 -
75 ± 1585 ± 15
1.4
60 ± 15
3.2 NR-B41MV2
Thermostat Dial Setting
Mean Fresh Food Compartment Temperature t3 (°C)
(°C)
(°C)
(°C)
(°C)
(°C)
(%)
Mean Freezer Load Temperature
Vegetable Crisper Temperature
PC Door Shelf Upper Temperature
Egg Tray Temperature
PC Door Shelf Bottom Temperature
Running Ratio
(kWh/Day)Power Consumption
“ 3 ” “ 2 ” “ 1 ”
1.0 ± 2.5 4.0 ± 2.5 7.0 ± 2.5
-22.0 ± 2.5 -19.5 ± 2.5 -16.0 ± 2.5
- 4.5 ± 2.5 -
- 6.0 ± 2.5 -
- 4.0 ± 2.5 -
- 5.0 ± 2.5 -
1.8
85 ± 15 75 ± 15 60 ± 15
NR-B37MV2 / NR-B41MV2

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4. SELF PROTECTING FUNCTION
4.1 Protection for IC
IC order to stop compressor completely.
YES
YES
After 1 hour.
SYSTEM PROTECT CONTROL CYCLE
1st time
OPERATE each 7min X 10 times
COMPRESSOR 1hour STOP OPERATE each 7min X 10 times
SYSTEM PROTECT CONTROL CYCLE
333rd time
STOP COMPRESSOR
NO
YES
YES
9
7
IC cancels to stop compressor.
Normal operating?
6
After restarting, does “Stop compressor”
occure 10 times within 2 min?
5
IC cancels to stop compressor.
Normal operating?
4
After 10 min., does PCB check if IPM protect
signal is normal?
3
Does system protection cycle for 333 times?
8
IC orders to stop compressor for 10 min.
2
Does IC receive IPM protect signal?
1
• IC continues to stop compressor until 1 hour.
• IC indicates Self Diagnosing sign.
NO
• IC continues to stop compressor until 1 hour.
• IC indicates Self Diagnosing sign.
NO
• Normal operating.
NR-B37MV2 / NR-B41MV2

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4.2 Protection for compressor locked
IC order to stop compressor completely.
YES
YES
After 1 hour.
SYSTEM PROTECT CONTROL CYCLE
1st time
OPERATE each 7min X 10 times
COMPRESSOR 1hour STOP OPERATE each 7min X 10 times
SYSTEM PROTECT CONTROL CYCLE
333rd time
STOP COMPRESSOR
NO
YES
8
6
7
IC cancels to stop compressor.
Normal operating?
5
After restarting, does “Stop compressor”
occure 10 times within 2 min.?
4
IC cancels to stop compressor after 10 min.
3
Does system protection cycle for 333 times?
IC orders to stop compressor for 10 min.
2
• After starting 2 sec., does IC detect
rpm < 5r/sec.?
• After starting from 2-10 sec., does PCB
detect rpm over 120r/sec.?
1
• IC continues to stop compressor until 1 hour.
• IC indicates Self Diagnosing sign.
NO
NO
• Normal operating.
NR-B37MV2 / NR-B41MV2

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4.3 Protection for power supply droping
YES
After 1 hour.
NO
YES
YES
7
IC cancels to stop compressor.
Normal operating?
6
After restarting, does “Stop compressor”
occure 10 times within 2 min?
5
IC cancels to stop compressor.
Normal operating?
4
After 10 min., does PCB check power supply
voltage if it is > 180V AC?
3
IC orders to stop compressor for 10 min.
2
Does power supply voltage drop as condition
> 0.1 sec. and < 160V AC?
1
• IC continues to stop compressor until 1 hour.
• IC indicates Self Diagnosing sign.
NO
• IC continues to stop compressor until 1 hour.
• IC indicates Self Diagnosing sign.
NO
• Normal operating.
NR-B37MV2 / NR-B41MV2

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5. SELF DIAGNOSING FUNCTION
1. Opening PC door and FC door,
Push “Quick Freezing” bottom more than 5 sec.
2. Blinking LED of “Energy Saving” and “Quick Freezing”
during 3 sec.
3. After blinking at 3 sec., each LED show as below.
How to use “Self Diagnosing” function
Symptom Details of symptom Energy Saving
LED
Quick Freezing
LED
Normal None None
Abnormal of FCC thermistor Break/Short of FCC thermistor None Blinking
Abnormal of DFC thermistor Break/Short of DFC thermistor None Turn on
Abnormal of ATC thermistor Break/Short of ATC thermistor Blinking Turn on
Abnormal of defrost heater in FC Break/Short of defrost heater Turn on None
Abnormal of INV compressor Operate protector of IPM lock
Operate protector of voltage dropping
Operate protector of over voltage
Turn on Blinking
Abnormal of FC fan motor Break/Lock of FC fan motor
Abnormal revolution of FC fan motor
Turn on Turn on
Abnormal of PCB Error of communication
Error of EEPROM
Blinking Blinking
NR-B37MV2 / NR-B41MV2
Energy Saving
Quick Freezing

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6. TEMPERATURE CONTROL
How to operate the “QUICK FREEZING” (Quick cool button)
If you want the refrigerator to freeze quickly in order to
preserve the food, press the “Quick Freezing” button
(green light LED turns on).
The system will operate immediately and will stop
operating automatically (green light LED turns off)
when it runs for 150 minutes.
And the operation will return to normal mode.
Remark
• If you want to stop the operation, press the “Quick Freezing”
button (green light LED turns off).
The system will return to normal mode.
• If the green light LED is flashing, it means that the defrosting
system is now working. The quick freezing system will start
the operation right after the defrosting operation is finished.
How to use the “ENERGY-SAVING” operation
When food storage is small or during nighttime and people out of home (when door opening frequency
is low), the “ENERGY-SAVING” operation saves electricity consumption by operating the compressor
at a lower speed than the normal operation.
How to save energy
• Press the “ENERGY SAVING” button. (green light turns on)
• Press the “ENERGY SAVING” button again to stop the operation. (green light turns off)
About energy saving
• Deodorizing function reduces.
• Interior temperature gets slightly higher.
• The “ENERGY SAVING” operation stops when the power cord is reconnected or after recovering from
a power failure.
• When the “ENERGY SAVING” is activated during “QUICK FREEZING”, the “ENERGY SAVING” starts
after completing the “QUICK FREEZING”
• Frequent opening of the doors raise the interior temperature.
(Higher interior temperature automatically activates normal operation on a temporary basis.)
NR-B37MV2 / NR-B41MV2
Energy Saving
button
Quick Freezing
button