DOWNLOAD Panasonic NR-BN30PGW / NR-BN30PGB / NR-BN30PS1 / NR-BN30QGW / NR-BN30QGB / NR-BN30QW1 / NR-BN30QS1 Service Manual ↓ Size: 1.23 MB | Pages: 40 in PDF or view online for FREE

Model
NR-BN30PGW NR-BN30PGB NR-BN30PS1 NR-BN30QGW NR-BN30QGB NR-BN30QW1 NR-BN30QS1
Pages
40
Size
1.23 MB
Type
PDF
Document
Service Manual
Brand
Device
Service Manual / Other / REFRIGERATOR-FREEZER
File
nr-bn30pgw-nr-bn30pgb-nr-bn30ps1-nr-bn30qgw-nr-bn3.pdf
Date

Panasonic NR-BN30PGW / NR-BN30PGB / NR-BN30PS1 / NR-BN30QGW / NR-BN30QGB / NR-BN30QW1 / NR-BN30QS1 Service Manual ▷ View online

 
 
13 
3) Touch and Feel 
a) Feel the compressor when running ,its temperature should be generally less than 90°C in the 
normal state (it may exceed 90°C in case of running for a longer period of time ). 
b) After the compressor has operated normally for 5~10 minutes , touch and feel the condenser ,the 
temperature of its upper part should be higher than that of its lower part (or its right part is hotter 
than its left part ,depending on the type of condenser coil ),this indicates that the refrigerant is 
circulating . If the condenser is not hot, this means the leakage of refrigerant .In case the condenser 
radiates heat for only several minutes and then cools down ,this means that the filter and capillary 
have been clogged .As for the forced air cooling condenser ,hot air will be blown out of it ;this means 
that the system is out of order . 
 
c) Feel the filter's temperature .During the normal operation of refrigerating system ,the temperature 
on the filter's surface should be a little higher than the ambient temperature ;if you touch it with your 
hand ,you will have a sense of slight heat .In case dew condensation appears due to the fact that its 
temperature is obviously lower than the ambient temperature ,this means that most meshes of its 
screen has been clogged ,resulting in an obstructed flowing of refrigerant ,thus causing a drop in 
temperature due to throttling . 
 
d) Feel the temperature of exhaust gas from the refrigerating system .the exhaust gas should be 
very hot and this is the normal working state .For those refrigerator with enclosed type of 
compressor refrigerating system, no frost or dew drop will from on the gas suction tube, 
otherwise ,there is something wrong in the system (Frosting and dew condensation may appear for 
a very short time period when just starting the machine ,this is a normal phenomenon ). Because a 
refrigerator is a combination of several components ,they are related and have influence on each 
other In case an abnormal phenomenon has been found through the above-mentioned 
checkups ,you need not to make a hasty conclusion based on only one abnormal phenomenon .It is 
advisable to find out two or more abnormal phenomenon ,or conduct troubleshooting 
comprehensively with the aid of instruments or other ways ,because several kinds of troubles may 
share a common abnormal phenomenon ,and two or more abnormal phenomena may occur 
simultaneously due to a certain trouble .With this method ,you can reject some suspicious troubles 
and finally make a correct judgment . 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
14 
7 Analysis of Troubles and Troubleshooting 
 
A. Poor Refrigerating Effect. 
The so-called "poor refrigerating effect " refers to the fact that the refrigerator can operate and 
refrigerator normally ,but the temperature in the refrigerator cannot drop to the prescribed value 
under the stipulated working conditions .In view of there are many causes for this phenomenon ,we 
are going to discuss and analyze it in the following 7 aspects : 
 
1) Leakage of refrigerant 
Analysis of Trouble 
The leakage of refrigerant in the system will result in an insufficient refrigerating capacity, the 
resulting phenomena are its lower gas suction pressure and exhaust pressure as well as higher 
exhaust gas temperature. The exhaust tube feels rather hot, and a continuous gas flowing sound 
louder than usual can be heard at the outlet of the 
capillary and no frost or a smaller quantity of loose frost appears on the evaporator .After shut 
down ,the balance pressure in the system is usually lower than the saturation pressure 
corresponding to the same ambient temperature . 
Remedy 
In case there is leakage of refrigerant from the system, do not hurry to recharge it with refrigerant, 
manage to find out leak points immediately, and make a note of from where it leaks ---welding points 
and parts .After having them repaired, recharge refrigerant . 
There are so many joints and sealed There are so surfaces in a refrigerator ,accordingly ,quite a lot 
potential leak points do exist in the system .In troubleshooting ,pay attention to those parts that are 
liable to leak ,check main connection points for oil seepage and tubing for cracks .If there is no 
severer leak point ,charge the system with nitrogen and detect leak points with the commonly 
adopted method ,repair them ,evacuate ,charge the system with refrigerant, and then turn on the 
refrigerator to make a test run . 
 
2) Too much refrigerant charged into the system 
Analysis of Trouble 
 
a) In case the amount of refrigerant charged into the system exceeds its nominal capacity ,the 
superfluous refrigerant will of course take some space of the evaporator ,thus reducing its 
heat-dissipation area and hence the refrigerating efficiency of the system .The abnormal 
phenomena caused by this reason are as follows :the gas suction and exhaust 
pressures are generally higher than their respective normal values ,the temperature of its condenser 
is higher and the electric current of the compressor rises ,loose frost forms on the evaporator ,the 
refrigerator temperature drops slowly ,and frost appears on the gas return tube . 
 
b) In case excessive refrigerant has been charged, the liquid refrigerant that cannot evaporates in 
the evaporator will return to the compressor and thus a phenomenon of "liquid striking" will 
occur .The liquid refrigerant evaporates and effervesces as soon as it flows into the refrigerating oil 
at the bottom of compressor .If the condition is severe ,foams will fill all over inside the compressor 
housing and be sucked by the piston ,causing damage to the components of compressor . 
Remedy 
According to the operating procedures ,it is mandatory to turn the machine off ,and several minutes 
 
 
15 
later ,open the refrigerant charging tube and et the refrigerant escape from it ,replace the dry 
filter ,recharge refrigerant after evacuating ,and then seal the charging port . 
 
3) There is air left in the refrigerating system Analysis of Trouble Residual air in the refrigerating 
system will reduce its refrigerating efficiency .The prominent phenomena are the increase in its gas 
suction and exhaust pressures (however ,the gas exhaust pressure will not exceed its rated 
value ),obvious increase in temperature in the segment from the compressor outlet to the condenser 
inlet .Because there is air in the system ,both the gas exhaust pressure and temperature will 
rise ,and moreover ,the gas flowing sound is intermittent and obviously louder . 
Remedy 
After shut down for several minutes, open the tubing, evacuate it and then recharge the system with 
refrigerant . 
 
4) Low efficiency of compressor 
Analysis of Trouble 
Low efficiency of a refrigerating compressor refers to the actual reduction of gas discharge 
capacity ,and hence the corresponding reduction of refrigerating capacity ,under the condition that 
the refrigerant in the system is unchanged .This phenomenon occurs mostly when the compressor 
has been used for quite a long time ,its moving parts have worn to a considerable degree ,fit 
clearance between various parts have increased and sealing property of its gas valve has 
deteriorated ,resulting in an decrease in its actual gas discharge capacity . 
Methods of Judgment 
Measure the high and low pressures with pressure gauges to see whether they are normal .If an 
abnormal sound comes from the compressor or the temperature of its causing is too high ,Cut the 
discharge port open and operate the compressor ,feel it if there is pressure at the discharge port 
with your finger (For a normal compressor ,its discharge port is difficult to be blocked with your finger 
if you just apply a little effort). 
 
5) Too thick frost layer formed on evaporator 
Analysis of Trouble 
If a direct cooling refrigerator is to be used for a prolonged period of time ,be sure to defrost its 
evaporator regularly ;if you fail to do so ,the frost layer on the evaporator tubing will become thicker 
and thicker .Heat conduction will be severely affected when the whole tubing is wrapped with a 
transparent ice layer ,and finally the temperature in the refrigerator cannot drop down to the 
prescribed range . 
Remedy Turn the refrigerator off, and make preparations for defrosting ,open the refrigerator door to 
let the air come in ,or use a fan to speed up air flowing so as to shorten the time needed for 
defrosting .Never strike the frost layer with any iron tools or wood stick in order to avoid damage to 
the evaporator tubing . 
 
6) Refrigerating oil left in evaporator tubing 
Analysis of Trouble During the process of refrigerating cycles, a little refrigerating oil may remain in 
the evaporator tubing and after a longer time of operation ,if there is considerable refrigerating oil left 
in the evaporator ,the heat conduction effect will be severely affected ,thus causing a poor 
refrigerating effect . 
Remedy It is quite difficult to determine whether this trouble is caused by the refrigerating oil left in 
 
 
16 
the evaporator tubing ,because this kind of phenomenon and other several trouble are tends to be 
confused .Generally speaking ,you can make a judgment based on the frost formed on the 
evaporator .If the frost does not cover the evaporator , and moreover ,it is loosely formed ,you can 
make a judgment that the deterioration of refrigerating effect is due to the accumulation of 
refrigerating oil left in the evaporator tubing in case no other troubles have been found . To clear off 
refrigerating oil left in the evaporator, dismantle the evaporator, purge it thoroughly and then dry it .In 
case it is difficult to dismantle it, charge 
refrigerant from the evaporator inlet to wash it several times ,then purge and dry it with nitrogen . 
 
7) Flowing obstructed in refrigerating system 
Analysis of Trouble 
Because the refrigerating system was originally not purged thoroughly ,some of the filter screen 
meshes have been clogged by dirt accumulated in the filter after using it for a certain time of 
period ,thus resulting in a decrease in flow rate ,and hence a poorer refrigerating effect . The 
abnormal phenomena caused by this kind of slight clogging in the system are as follows: the gas 
discharge pressure is lower, the temperature of discharged gas drops down, the position clogged 
has a temperature lower than that in normal conditions and for a severe clogging ,even dew 
condensation as frosting may appear . 
Remedy 
Purge the tubing, and after replacing the dry filter with a new one or clearing it thoroughly, recharge 
the system with refrigerant and seal the charging port . 
 
B. No Refrigerating 
The phenomenon that the compressor runs normally, but refrigerator temperature does not drop 
down is called "no refrigerating". There are many causes for this trouble and it is relatively 
complicated, too. In servicing, special attention to finding direct causes for this phenomenon .Three 
main potential causes for this trouble are analyzed below: 
 
1) All refrigerant in the system has leaked out 
Analysis of Trouble 
Leak points in the refrigerating system have not been found and repaired timely, thus resulting in the 
total escape of refrigerant .There are two kinds of leakage: 
 
I) slow leakage for instance, when we want to use a refrigerator that has been put out of quite a 
long time, we find the leakage of refrigerant, or in the course of its operation, we have found that the 
refrigerator is gradually becoming not so cold and finally no refrigerating cab be achieved ;   
 
ii) fast leakage in that case, all the refrigerant will escape swiftly due to abrupt rupture of system 
tubing . Symptoms of total leakage of refrigerant are mainly as follows: the compressor can be 
started easily (if there is no damage to the compressor parts) and its operating current becomes low, 
its gas suction pressure is high and discharge pressure is lower, the gas discharge tube feels rather 
cold, no sound of gas eruption from the liquid in the evaporator can be
 
heard, and no will gush out of 
the process tube if you cut it open after shutdown. 
Remedy 
Check the whole machine, particularly those locations which are liable to leak .After leak points have 
been found, repair them or replace them with new parts according to specific circumstances, then 
Page of 40
Display

Click on the first or last page to see other NR-BN30PGW / NR-BN30PGB / NR-BN30PS1 / NR-BN30QGW / NR-BN30QGB / NR-BN30QW1 / NR-BN30QS1 service manuals if exist.