LG GR-322W 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 defects have been found, empty the old
system of possible R-134a 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 complete extension with male Hansen and
at 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 defects have been found, empty the old
system of possible R-134a 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 complete extension with male Hansen and
at 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 the heating the of 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 the heating the of 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 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 it will be
necessary to stop the vacuum pump and to add asmall
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 it will be
necessary to stop the vacuum pump and to add asmall
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-134a to the refrigeration system. Remember that every
system has an exact quantity of R-134a with a tolerance of
±5 grams that can be added. (Figure 4)
R-134a to the refrigeration system. Remember that every
system has an exact quantity of R-134a 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 the refilling tube are
closed in order to keep the Freon for addition to the system.
(Figure 5)
refilling cylinder are connected), make sure that the valve
placed between the vacuum pump and the refilling tube are
closed in order to keep the Freon for addition to the system.
(Figure 5)
In addition, check the graduated scale on the cylinder for
the quantity of R-134a to be added, for example, if we
have 750 grams of Freon in the cylinder and must add 140
grams to the group, this amount will be reached when
R-134a has dropped to 610 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-134a 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 the 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 lowering the pressure again. Regulate
the valve again, maintaining the same manner until
reaching to the quantity of R-134a 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-134a to be added, for example, if we
have 750 grams of Freon in the cylinder and must add 140
grams to the group, this amount will be reached when
R-134a has dropped to 610 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-134a 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 the 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 lowering the pressure again. Regulate
the valve again, maintaining the same manner until
reaching to the quantity of R-134a 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.
SERVICING PRECAUTIONS
- 3 -
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-134a 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
6-1 COMPRESSOR AND ELECTRIC COMPONENTS
6. TROUBLESHOOTING
- 10 -
1
2
3
4
5
2
5
5
3
4
5
5
1
4
3
YES
YES
YES
NO
YES
YES
NO
NO
5
YES
NO
YES
Power Source.
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.
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%.
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
Normal operation of
Compressor is
impossible or poor.
Compressor is
impossible or poor.
Separate the PTC from
Compressor and
measure the
resistance between
No. 5 and 6 of PTC
with a Tester or
Whistone Bridge.
(Figure 23)
Compressor and
measure the
resistance between
No. 5 and 6 of PTC
with a Tester or
Whistone Bridge.
(Figure 23)
Separate the OLP from
Compressor and check
resistance value
between two terminals
of OLP with a Tester.
(Figure 24)
Compressor and check
resistance value
between two terminals
of OLP with a Tester.
(Figure 24)
Observation value is
220V/50Hz : 22
220V/50Hz : 22
Ω
±30%
115V/60Hz : 6.8
Ω
±30%
240V/50Hz : 33
Ω
±30%
127, 220V/60Hz : 22
Ω
±30%
The resistance
value is
0 or several
hundreds
value is
0 or several
hundreds
Ω
.
The value is
∞
.
Check another
electric components.
electric components.
Replace OLP.
Check another
electric components.
electric components.
Replace
PTC.
PTC.
Figure 23
Figure 24
6-3 DEFROST TIMER
- 12 -
NO
Cam Shaft
NO
YES
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 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 25).
to the point of first "click"
sound and check the
current 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 25).
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
Ω
or variable.
The resistance is about
220V/50Hz : 20K
220V/50Hz : 20K
Ω
115V/60Hz : 7.8K
Ω
Loud "click" sound.
Replace the
Defrost Timer.
Defrost Timer.
Replace the
Defrost Timer.
Defrost Timer.
Check the other
electric components.
electric components.
Replace the
Defrost Timer.
Defrost Timer.
Replace the
Defrost Timer.
Defrost Timer.
Figure 25
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