Premium PFR70800M User manual

000
This product is for domestic use only
Use & care manual
Important safeguards
Service Manual
CHEST FREEZER
SUPER DESIGN
MODEL: PFR70800M

CONTENT
1. Content}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}.
1
2. Product code illumination and Series Introduction}}2
3. Specifications
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. 3
4. Safety
precautions
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... 4
5. Function
Schedule
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. 7
6. System Flow Chart
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8
7. Circuit Diagram
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9
8. Maintenance Service and Trouble Shooting
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... 10
1

Specifications
Specifications
Models
Net capacity
(L)
PFR7080M
198
Color
White
Power Supply
(V/Hz)
115~/60
Rated Input Power
(W)
90
Power Consumption
(kW.·h/24h)
0.76
Net Weight
(kg)
32
Gross Weight
(kg)
Unit Dimension
(D*W*H)
(mm)
Packing Dimension
(D*W*H)
(mm)
Container Quantity
40'HQ
(PCS)
35
945*523*850
985*545*885
144
3

Safety precautions
Safety precautions
4
115V~/60Hz AC

Safety precautions
5

Safety precautions
6

Function Schedule
Function Schedule
ƽ
Energy efficiency
ƽ
Micro foam technology
ƽ
Low noise operation
ƽThick insulation for energy efficiency
7

System Flow Chart
System Flow Chart
1 Schematic diagram of System Flow Chart
2 Brief Description of System Flow Chart
It
is a direct cooling single
-system Freezer.
When the
Freezer is just powered on, the refrigerant flows in the
sequence: 1->2->3-
>4
->5>1
8

Circuit Diagram
Circuit Diagram
1
Schematic Circuit Diagram
See the rating label on the Freezer.
Brief Description of Control Principle
It is a direct cooling single
-system Freezer
with a small ice box. a mechanical type of
all the control is
generally adopted. The thermostat
directly controls the start
and stop of
compressor, and hence the Freezer temperature.
9

Maintenance Service and Trouble Shooting
Maintenance Service and Trouble Shooting
1. No cooling
No cooling
If compressor
can run after it stop to
run five minutes and
give power.
NO
Check and repair according to
the section of "the compessor
doesn't work".
YES
If compressor
can run naturally and
temperature raising
of condenser is
very low
YES
NO
Refrigerant
leak,check and
repair charge
refrigerant a
gain.
Block by ice or dirty
things,change filter and change
refrigerant again.
!
When charging refrigerant,we must
notice to make refrigerant true.
10

Maintenance Service and Trouble Shooting
2 The compressor doesn't stop
Compressor doesn't
stop
Does the Freezer
refrgerate?
NO
Check and repair according to
the section of "No cooling".
YES
Is cooling capacity
insufficient.
NO
Check and repair according to
the section of "Cooling capacity
is insuffcient".
YES
1 The thermostat was
set at the coldest position.
2 The ambient temperature is very high or
the
Freezer is near by heat resource.
3 The door was opened too many
times or there are more
fresh food inside.
NO
Adjust and instruct
consumer how to use.
NO
Check and repair the main
control panel
11

Maintenance Service and Trouble Shooting
3 Cooling capacity is insufficient
Cooling capacity is
insufficient
Is the
ambient YES
temperature low than
16eC
Check the therostat is
correct?
YES
NO
Does the refrigerant
leak siowly?.
Adjust and instruct
consumer how to use.
Repair
12

Maintenance Service and Trouble Shooting
4 The compressor doesn't work
The compressor doesn't
work.
Does the refrigerated
room lamp illuminate
when the door is
opened?
NO
Check the power
source and power
cord?
NO
Repair
YES
YES
Is the ambient
temperature low than
16
YES
Check the therostat is
correct?
Adjust and instruct
consumer how to use.
Does the control
panel has 220V power
output?
NO
Check and repair the
control panel.
YES
Does the compressor
has 220V power
output?
NO
Check all cords and
power cords.
YES
Check and repair
compressor and accessory.
13

Maintenance Service and Trouble Shooting
5 Normal Phenomena
—Not Troubles for Freezers
In a domestic Freezer, there is not only a complicated electric control
system, but also a refrigerating system that is difficult to discern whether it
is in a good working condition. Both the systems are related and
affect
each other.
If a certain part of a Freezer works abnormally .Its
refrigerating efficiency will decrease ,operation properties
will become
unstable ,or even it cannot be used normally for those serious cases.
Freezers are generally of larger volume ,once troubles appear ,to
send them to a service department is really a tough thing ,if such is the
case ,the user will always be in suspense ,sometimes ,normal phenomena
will be erroneously regarded as troubles .Therefore ,before we deal
with
the topics of frequently
occurring troubles of Freezers and their
remedies ,we should firstly
give a brief account of some normal
phenomena which are not troubles .In case any one of such phenomena
occurs ,there is no need to worry about it ,and the user can use it at total
ease .
1).When the compressor of a Freezer has just stopped running ,a
rumbling sound can be heard from inside its evaporator .This is a sound
caused by the flowing of refrigerant in the evaporator tubing .Because the
pressure difference is still greate
r after the compressor has just stopped
running ,the refrigerant will flow for a certain time , therefore ,this sound is a
normal phenomenon.
2).A click sound can often be heard from the Freezer .This is a
normal
sound produced by the pull-in or release of the armature of a
current deadweight start relay when starting the compressor
.The
compres
sor motor will produce a slight and uniform sound while it is
running .This sound is not easy to be heard in the daytime ,but of course it
can be heard disti
nctly at night.
3).The compressor consists of an electric motor and a compressing
apparatus .During its normal operatio ,the motor's stator core
and
windings will rise to a t
emperature in the range of 100eC~110eC ,and the
temperature of the piston and
cylinder of the compressing mechanism can
also reach as above 100
eC due to the heat produced when compressing
refrigerant .Most of the heat radiates to
the air through the compressor
casing ,therefore ,its casing is generally at a temperature between 85
e
C ~90eC
,it is very hot ,particularly in summer when the ambient temperature is
higher .All these are normal phenomena .
4).For the direct cooling Freezer ,a kind of irregular crack sound can
be often heard when the compressor is running for a certain period of time
or has just stopped its running .This sound is caused by the stress relief
due to expansion and contraction when temperature changes ,and will not
affect the normal application of Freezer .
14

Maintenance Service and Trouble Shooting
6 Common Troubles in
Freezers and Their Remedies
Causes for troubles occurring in Freezers are closely related to the
quality of components and workmanship in assembling by manufacturers
as whether
Freezer
s are properly used and maintained .The parameters
generally used to express the working conditions of a
Freezer include
the
temperature inside the Freezer ,operation rate ,electric
power
consumption ,noise level ,and other functional indexes .If any one of these
parameters is beyond its permissib
le range ,this indicates that there is a
fault or trouble in the
Freezer .
During the whole service life of a Freezer ,
the probability of troubles
occurring within a union time is called its failure rate .Making a comparison
between the control circu
it system of a Freezer and its refrigerating
system ,we can find that the failure rate of the former is higher ,and that of
the thermostat is the highest . In troubleshooting ,
the first thing you must do
is to determine where the trouble comes from
--- the control system or the
refrigerating system .There is general no
trouble indicating instrument
mounted on the
dome stic Freezer ,locations and natures of troubles
should be determined according to their
respective
features ,therefore ,experience in
servicing is
very important to
troubleshooting.
Service technicians with rich experience can correctly
locate them and take reasonable remedy measures based on
their
comprehensive analysis of trouble characteristics as well as
operating
conditions for
various kinds of Freezers .
Three Essentials for Checkup
1) Look
a) Check the tubing of refrigerating system for cracks and various
welding points for leaks ;if leakage occurs ,an oil stain can be
seen
definitely .
b) Check the suction and exhaust pressure values (high pressure and
low pressure) of compressor to see whether they are normal .
c) Check the conditions of frost attached to its evaporator and gas
return tube .It is abnormal if frost has formed on part of the evaporator or
there
is no frost attached to it .
d) Pay attention to the speed of temperature drop inside freezer
compartment .It is abnormal if the speed of temperature drop is obviously
slower than the corresponding normal speed .
e) Check the environment to see whether it is suitable for placing a
Freezer .
f)
layer .
Check
Freezer door seal ,case ,table surface and heat insulation
g) Look at the main control board to ascertain if various indication
states are normal.
2) Listen
a) Listen to the noises produced when the compressor is running
15

Maintenance Service and Trouble Shooting
Hums from a fully enclosed aggregate unit is the sound caused by
overload indicating that the motor cannot be started normally ,meanwhile ,a
clattering sound can be h
eard from inside the start relay ,which is produced
because the start contacts cannot be released normally .A whistling sound
is caused by the high pressure gas flowing out of the crack of the pressure
tube inside the compressor ,and clucks are the soun
d of striking after the
suspend
ed spring inside the compressor has broken .
During the normal operation of compressor, a slight and uniform hum
sound due to undulation of electric current can be heard generally ,this is a
normal phenomenon .However ,if
it sounds like "tong ,tong }",i.e., an
impact sound inside the compressor ,this means that a large quantity of wet
vapour of refrigerant or refrigerating oil has come into the
compressor
cylinder ;if it sounds like "dang
,dang}", a striking sound of metal parts
inside the compressor ,this means that some moving parts have loosened
(note to differentiate this sound from those formed during starting
or
stopping the compressor).
b) Listen to the sound caused by the flowing of gas in the evaporator
Open the Freezer door while the compressor is in operation, incline
your ear and listen attentively the gas flow sound inside the evaporator .If it
sounds like gentle whistling accompanied by a sound similar to
water
flowing ,this is the sound produced by
the normal circulation of refrigerant
within the evaporator .In case only the gas flowing sound can be heard and
there is no water flowing sound ,this indicates that the refrigerant
has
already percolated .If neither the flowing sound nor the gas sounds
from
the evaporator can be heard ,this means that the filter or capillary has been
clogged .
3)Touch and Feel
a) Feel the compressor when running ,its temperature should be
generally less than 90
eC in the n
ormal state (it may exceed
90eC in case
of running for a longer period of time ).
b) After the compressor has operated normally for 5~10 minutes ,
ouch 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
16

Maintenance Service and Trouble Shooting
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 du
e 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
Freezer with enclosed type of compressor refrigerating
system, no frost or dew d
rop 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
Freezer 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 advi
sable 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 oc
cur simultaneously due to a certain trouble .With this method ,you
can reject some suspicious troubles and finally make a correct judgment .
7 Analysis of Troubles and Troubleshooting
A. Poor Refrigerating Effect
The so-called "poor refrigerating effect " refers to the fact that the
Freezer
can operate and Freezer normally ,but the temperature in
the
Freezer cannot drop to the prescribed value under the stipulated
working conditions .In view of there are many causes for this
phenomenon ,we are goi
ng 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 f
rost 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 .
17

Maintenance Service and Trouble Shooting
many joints and sealed surfaces in a
There
are
so
Freezer ,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
Freezer
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 redu
cing 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
temper
ature of its condenser is higher and the electric current of the
compressor rises ,loose frost forms on the evaporator ,the
Freezer
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 p
henomenon of "liquid striking" will occur .The
liquid refrigerant evaporates and effervesces as soon as it flows into the
refrigerating oil at t
he 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
achine off ,and several minutes 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 inte
rmittent 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
18

Maintenance Service and Trouble Shooting
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 a
n 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 Freezer 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
Freezer
cannot drop down to the prescribed range .
Remedy
Turn the Freezer off , and make preparations for defrosting ,open the
Freezer
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 dama
ge 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
refrigerati
ng oil left in 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
loose
ly formed ,you can make a judgment that the deterioration of
19

Maintenance Service and Trouble Shooting
refrigerating effect is due to the accumulation of refrigerating oil left in the
evaporator tubing in case no oth
er 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 seve
ral 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
acc
umulated 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 no frost (or
only a little fr
ost ) appears on the evaporator ,and the Freezer
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 t
he total escape of refrigerant .There are
two kinds of leakage :I)
slow leakage for instance ,when we want to use a
Freezer
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
Freezer
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 asfollows : 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
col
d ,no sound of gas eruption from the liquid in the evaporator can be
20