LG GR-392CVF Service Manual ▷ View online
AIR RECHARGING IN COMPRESSOR
Test the refrigeration system connecting it electrically before
refilling operation. It is necessary to ascertain the function
of the motor-compressor and identify the defects
immediately. If the defects have been found, empty the old
system of eventual R-12(R134a) residue by breaking off the
end of the extension piece at its narrow point. (Figure 1)
Replace the filter and any damaged components. Unsolder
and pull off the piece remaining inside the service tube and
then attach an extension completely with male Hansen and
last, solder it to the same tube again. (Figure 2)
refilling operation. It is necessary to ascertain the function
of the motor-compressor and identify the defects
immediately. If the defects have been found, empty the old
system of eventual R-12(R134a) residue by breaking off the
end of the extension piece at its narrow point. (Figure 1)
Replace the filter and any damaged components. Unsolder
and pull off the piece remaining inside the service tube and
then attach an extension completely with male Hansen and
last, solder it to the same tube again. (Figure 2)
It is necessary to execute the soldering operation with
valve open so that the fumes caused by oil residue can
come out freely without blowholes between two tubes
during heating the point to be soldered.
The extension fitted with the male Hansen is connected to
the female fitting of the vacuum pump tube. (Figure 3)
valve open so that the fumes caused by oil residue can
come out freely without blowholes between two tubes
during heating the point to be soldered.
The extension fitted with the male Hansen is connected to
the female fitting of the vacuum pump tube. (Figure 3)
Air evacuating from the system begins so soon as the
pump starts. The refrigeration system must be kept under
vacuum until the reading on the low-pressure gauge
indicates vacuum (0 absolute, -1 atm., -760 mm hg) in any
case it is advisable to keep the pump running for about 30
minutes. (Figure 3)
In case that a considerable leakage occurs and to stop the
vacuum pump will be necessary and add a small quantity
of Freon to the system, if vacuum should not be obtained
(pressure gauge can't fall to 1 atmosphere), start the
refrigeration unit and find the leakage with the special leak-
finder. When the defective soldering point is visible, re-do it
after opening the extension tube valve and reestablishing
the normal outside pressure inside the group.
Because the melted alloy is sucked into the tubes and
block them, the pressure must be rebalanced when
vacuum is in the system in soldering. As soon as the
pump starts. The refrigeration system must be kept under
vacuum until the reading on the low-pressure gauge
indicates vacuum (0 absolute, -1 atm., -760 mm hg) in any
case it is advisable to keep the pump running for about 30
minutes. (Figure 3)
In case that a considerable leakage occurs and to stop the
vacuum pump will be necessary and add a small quantity
of Freon to the system, if vacuum should not be obtained
(pressure gauge can't fall to 1 atmosphere), start the
refrigeration unit and find the leakage with the special leak-
finder. When the defective soldering point is visible, re-do it
after opening the extension tube valve and reestablishing
the normal outside pressure inside the group.
Because the melted alloy is sucked into the tubes and
block them, the pressure must be rebalanced when
vacuum is in the system in soldering. As soon as the
vacuum operation is over, add the quantity in grams of
R-12(R134a) to the refrigerant system. Remember that
every system has an exact quantity of R-12(R134a) with a
tolerance of ±5 grams that can be added. (Figure 4)
R-12(R134a) to the refrigerant system. Remember that
every system has an exact quantity of R-12(R134a) with a
tolerance of ±5 grams that can be added. (Figure 4)
Before performing this operation (if the vacuum pump and
refilling cylinder are connected), make sure that the valve
placed between the vacuum pump and refilling tube are
closed to keep the Freon for adding to the system. (Figure 5)
refilling cylinder are connected), make sure that the valve
placed between the vacuum pump and refilling tube are
closed to keep the Freon for adding to the system. (Figure 5)
In addition, check the graduated scale on the cylinder for
the quantity of R-12(R134a) to be added, for example, if we
have 750 grams of Freon in the cylinder and must add 165
grams to the group, this amount will be reached when
R-12(R134a) has dropped to 585 grams, remembering that
the indicator shows a lower limit of meniscus. Do this after
choosing the scale corresponding to the gas pressure
different scales reported as the same gas pressure
indicated by the pressure gauge on the top of the column.
To make R-12(R134a) flow into the system, open the valve
placed at the base of the cylinder and connected to the
filling tube. The amount of Freon cannot be added to the
system all at once because it may cause a blocking of motor-
compressor. Therefore, proceed by adding original quantity
of about 20-30 grams and close the valve immediately.
The pressure rises and the motor-compressor must start,
sucking the gas and making the pressure go down again.
Regulate the valve again, maintaining the same manner
until reaching to the quantity of R-12(R134a) established
for the system being charged. When the system is running,
the suction pressure must be stabilized between 0.30 to
0.6(0.10 to 0.4) atmosphere.
the quantity of R-12(R134a) to be added, for example, if we
have 750 grams of Freon in the cylinder and must add 165
grams to the group, this amount will be reached when
R-12(R134a) has dropped to 585 grams, remembering that
the indicator shows a lower limit of meniscus. Do this after
choosing the scale corresponding to the gas pressure
different scales reported as the same gas pressure
indicated by the pressure gauge on the top of the column.
To make R-12(R134a) flow into the system, open the valve
placed at the base of the cylinder and connected to the
filling tube. The amount of Freon cannot be added to the
system all at once because it may cause a blocking of motor-
compressor. Therefore, proceed by adding original quantity
of about 20-30 grams and close the valve immediately.
The pressure rises and the motor-compressor must start,
sucking the gas and making the pressure go down again.
Regulate the valve again, maintaining the same manner
until reaching to the quantity of R-12(R134a) established
for the system being charged. When the system is running,
the suction pressure must be stabilized between 0.30 to
0.6(0.10 to 0.4) atmosphere.
POINT TO BE BROKEN
SERVICE TUBE EXTENSION
CHARGE TUBE
EXTENSION
EXTENSION
FEMALE
HANSEN
HANSEN
MALE HANSEN
SOLDERING POINT
Figure 1
Figure 2
TO THE
VACUUM
PUMP
VACUUM
PUMP
PRESSURE
GAUGE
GAUGE
Figure 3
TO THE R-12(R134a) CYLINDER
TO THE REFRIGERATION
SYSTEM
SYSTEM
Figure 4
FILLING OR
CHARGE TUBE
CHARGE TUBE
VALVE TO BE OPENED
WHEN REFILLING
WHEN REFILLING
VALVE TO BE CLOSED
AFTER VACUUM
AFTER VACUUM
TO THE CHARGE
CYLINDER
CYLINDER
TO THE REFRIGERATION
SYSTEM
SYSTEM
TO THE
VACUUM
PUMP
VACUUM
PUMP
Figure 5
SERVICING PRECAUTIONS
- 3 -
6-1 COMPRESSOR AND ELECTRIC COMPONENTS
6. TROUBLESHOOTING
- 10 -
1-
-
-
2-
3-
4-
5-
2-
5-
5-
3-
5-
4-
5-
5-
1-
-
-
4-
3-
YES-
YES-
YES-
YES-
NO-
NO-
YES-
YES-
YES-
NO-
NO-
NO-
Power Source.
No Voltage.
(Rating Voltage
±10%)?
±10%)?
Replace OLP.
Reconnect.
Replace
PTC-Starter.
PTC-Starter.
Replace OLP.
O.K.
Check connection
condition.
condition.
OLP disconnected?
Advise the customer
to use a regular
TRANS.
to use a regular
TRANS.
Replace Compressor.
OLP works within
30 sec. in forcible OLP
operation by turning
instant power on and
off.
30 sec. in forcible OLP
operation by turning
instant power on and
off.
Components start in
the voltage of Rating
Voltage ±10%
below.
the voltage of Rating
Voltage ±10%
below.
Applied voltage isn't
in the range of Rating
Voltage ±10%.
in the range of Rating
Voltage ±10%.
Remove the PTC-
Starter from the
Compressor and
measure the voltage
between Terminal C of
Compressor and
Terminals 5 or 6 of PTC.
Starter from the
Compressor and
measure the voltage
between Terminal C of
Compressor and
Terminals 5 or 6 of PTC.
Check the resistance
among M-C, S-C and
M-S in Motor
Compressor.
among M-C, S-C and
M-S in Motor
Compressor.
Check the resistance
of two terminals in
PTC-Starter.
of two terminals in
PTC-Starter.
Check if applying
a regular OLP.
a regular OLP.
Measure minimum
starting voltage after 5
min. for balancing cycle
pressure and cooling the
PTC.
starting voltage after 5
min. for balancing cycle
pressure and cooling the
PTC.
Check the
resistance of
Motor
Compressor.
resistance of
Motor
Compressor.
Check the
resistance of
PTC-Starter.
resistance of
PTC-Starter.
Check OLP.
Check
starting state.
starting state.
6-2 PTC AND OLP
- 11 -
6-
5-
YES-
NO-
NO-
YES-
NO-
Cam Shaft-
Normal operation of
Compressor is
impossible or poor.
Compressor is
impossible or poor.
Separate the PTC-
Starter from
Compressor and
measure the
resistance between
No. 5 and 6 of PTC-
Starter with a Tester or
Whistone Bridge.
(Figure 21)
Starter from
Compressor and
measure the
resistance between
No. 5 and 6 of PTC-
Starter with a Tester or
Whistone Bridge.
(Figure 21)
Separate the OLP from
Compressor and check
the resistance value
between two terminals
of OLP with a Tester.
(Figure 22)
Compressor and check
the resistance value
between two terminals
of OLP with a Tester.
(Figure 22)
Observation value is
220V/50Hz : 22
220V/50Hz : 22
§
±30%
115V/60Hz : 6.8
§
±30%
240V/50Hz : 33
§
±30%
127, 220V/60Hz : 22
§
±30%
The resistance value
is 0 or several
hundreds
is 0 or several
hundreds
§
.
The value is
¡˜
.
Check another
electric components.
electric components.
Replace OLP.
Check another
electric components.
electric components.
Replace PTC-
Starter
Starter
Figure 21
Figure 22
Figure 23
Normal operation of
the Defrost Timer is
impossible.
the Defrost Timer is
impossible.
No defrosting.
Poor cooling.
Position the Cam Shaft to
the point of first 'click'
sound and check the
current flowing between
terminals No. 1(brown)
and No. 2(bright orange).
Next, position the Cam
Shaft to the point of
second "click" sound and
check the current flowing
between terminals
No. 1(brown) and
No. 4(black)
(Figure 23).
the point of first 'click'
sound and check the
current flowing between
terminals No. 1(brown)
and No. 2(bright orange).
Next, position the Cam
Shaft to the point of
second "click" sound and
check the current flowing
between terminals
No. 1(brown) and
No. 4(black)
(Figure 23).
Turn the Cam Shaft.
Shake about 3 times
with holding the Cam
Shaft and Body softly.
with holding the Cam
Shaft and Body softly.
The resistance is
¡˜
The resistance is
0
0
§
or variable.
The resistance is about
220V/50Hz : 20K
220V/50Hz : 20K
§
115V/60Hz : 7.8K
§ .
Loud 'click' sound.
Replace the
Defrost Timer.
Defrost Timer.
Replace the
Defrost Timer.
Defrost Timer.
Replace the
Defrost Timer.
Defrost Timer.
Check the another
electric components.
electric components.
Replace the
Defrost Timer.
Defrost Timer.
6-3 DEFROST TIMER
6-4 ANOTHER ELECTRIC COMPONENTS
- 12 -
▼ Cooling is impossible
Compressor
doesn't run.
doesn't run.
Running state of
Compressor is poor.
Compressor is poor.
Check a starting
voltage.
voltage.
Check if current flows to
the following
components.
the following
components.
a. Thermostat
b. Starting devices
c. OLP
d. Compressor coil
e. Defrost Timer
f. Circuit parts
Low voltage.
Poor contacting and
gas leakage.
gas leakage.
Shorted or broken.
Poor contacting
or shorted.
or shorted.
Coil shorted.
Poor contacting
or shorted.
or shorted.
Poor contacting
and broken.
and broken.
Shorted.
Lack of capacity.
Coil of motor
Compressor.
Compressor.
Replace
the compressor.
the compressor.
Replace
each component.
each component.
Raise the voltage.
Replace
each component.
each component.
Cause
Check if current flows
to starting devices.
to starting devices.
Check current flowing
in sub-coil of
Compressor.
in sub-coil of
Compressor.
Check capacity of OLP.
The items described
above are normal.
above are normal.
▼ Cooling ability is poor
Fan motor
doesn't run.
doesn't run.
Much frost are sticked
to the EVAPORATOR.
to the EVAPORATOR.
Poor contacting.
Coil is shorted.
Shorted.
Replace
each component.
each component.
Replace
each component.
each component.
Replace
each component.
each component.
Running is poor.
(Coil is shorted.)
(Coil is shorted.)
Check current flowing
of the door S/W.
of the door S/W.
Check current flowing
in the Fan Motor.
in the Fan Motor.
Check the running
condition of Timer.
condition of Timer.
Check current flowing
of the following
components.
¥ Defrost Thermostat
¥ Fuse-M
of the following
components.
¥ Defrost Thermostat
¥ Fuse-M
Check current flowing
of the following
components.
¥ L-cord
¥ TE-Plate Heater
of the following
components.
¥ L-cord
¥ TE-Plate Heater
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