LG GR-154 series, Руководство по обслуживанию

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SERVICING PRECAUTIONS
-3-
Features of refrigerant (R600a)
• Achromatic and odor less gas.
• Flammable gas and the ignition (explosion) at 494°C.
• Upper/lower explosion limit: 1.8%~8.4%/Vol.
Features of the R600a refrigerator
• Charging of 60% refrigerant compared with a R134a model
• The suction pressure is below 1bar (abs) during the operation.
• Because of its low suction pressure, the external air may flow in the cycle
system when the refrigerant leak, and it causes malfunction in the compressor.
• The displacement of compressor using R600a must be at least 1.7 times larger
than that of R134a.
• Drier type is XH-9.
• The EVAPORATOR or any other cycle part that has welding joint is hidden in
the foam. (If not hidden inside, the whole electric parts must be tested with the
LEAKAGE TEST according to the IEC Standard.)
• The compressor has label of the refrigerant R600a.
• Only the Service man must have an access to the system.
Installation place
• Must be well ventilated.
• Must be 20 m
3 or larger.
• Must be no-smoking area.
• No ignitable factors must be present.
Utilities
• Refrigerant cylinder (MAX NET 300g)
• Manometer
• Vacuum pump (600L/min)
• Piercing Clamp
• Quick coupler
• Hoses (5m-1EA, 1m-3EA)
• LOKRING
• Portable Leakage detector (3g/year¯)
• Nitrogen cylinder (for leakage test)
• Concentration gauge
Make sure before Servicing
• Refrigerant
Confirm the refrigerant by checking Name Plate on innerliner and the label on
the compressor.
• If the refrigerant is R600a, you must not weld or apply a heat source.
Air Recharging in Compressor
Before refilling the refrigerant, you must perform the test according to Chapter 5
(TROUBLESHOOTING CHART). When the defects are found, you must
discharge the residual refrigerant (R600a) in the outdoor. For discharging the
refrigerant R600a, break the narrow portion of tube extension by hand or with a
pipe cutter as shown in Figure 1. Leave it for 30min in outside to stabilize the
pressure with ambient. Then, check the pressure by piercing the dryer part with
piercing pliers. If the refrigerant is not completely discharged, let the refrigerator
alone for more 30min in outside.
Attach the service tube installed with a Schrader valve (one-way
valve) by using the LOKRING (Figure 2). Then, connect the
Schrader valve (one-way valve) to the pump that is connected to
the discharging hose leading to the outside. When discharging the
residual refrigerant, repeat 3 cycle that includes 3min of the pump
running->pump off->30sec of the compressor running.
After the refrigerant (R600a) is completely discharged, repair any
defective parts and replace the dryer. At any case you must use the
LOKRING for connecting or replacing any part in the cycle (No Fire,
No Welding). Connect the Schrader valve to pump with the coupler.
And then turn the pump on for vacuum state (Figure 3). Let the
pump run until the low-pressure gauge indicates the vacuum (gauge
pressure 0, absolute pressure -1atm or -760mmHg). Recommended
vacuum time is 30 min. Charge the N2 gas in order to check for
leakage from welding points and the LOKRING. If leakages are
found, repair the defects and repeat the vacuum process.
After the system is completely vacuumed, fill it with the refrigerant
R600a up to what has been specified at your refrigerator Name
Plate. The amount of refrigerant (R600a) must be precisely
measured within the error of ±1g by an electron scale (Figure 4).
If you use the manifold connected with both the refrigerant
(R600a) cylinder and the vacuum pump simultaneously,
make sure the pump valve is closed (Figure 5).
Connect the charging hose (that is connected to the refrigerant (R600a) cylinder) to
the Schrader valve installed on the service tube. Then, charge the refrigerant (R600a)
by controlling the Throttle valve. When you do so, do not fully open the Throttle valve
because it may make damage to the compressor. Gradually charge the refrigerant
(R600a) by changing open and close the Throttle Valve (5g at each time). The
charging hose must use a one-way valve to prevent the refrigerant refluence. Close
the Schrader valve cap after the refrigerant (R600a) is completely recharged.
After you completely recharge the refrigerant (R600a), perform the leakage test by
using a portable leakage detector or soapy water.
Test the low pressure (suction) parts in compressor off time and high pressure parts
in compressor on time. If the leakages are found, restart from the refrigerant (R600a)
discharging process and repairs defects of leaks.
After the leakage test, check the temperature of each parts of the cycle. Check with
hands if the CONDENSER and the case (HOT-LINE pipe) that is contacted to the
door gasket are warm. Confirm that frost is uniform distributed on the surface of
the freezer room and the back wall of fridge room.
POINT TO BE
BROKEN
CHARGE TUBE
EXTENSION
SCHRADER VALVE
(ONE-WAY VALVE)
LOKRING
SERVICE TUBE
EXTENSION
Figure 1 Figure 2
TO THE
VACUUM
PUMP
PRESSURE
GAUGE
Figure 3
WEIGH SCALE
THROTTLE
VALVE
COUPLE
REFRIGERANT
(R600a)
CHARGING HOSE
Figure 4
FILLING OR
CHARGE TUBE VALVE TO BE OPENED
WHEN REFILLING
VALVE TO BE CLOSED
AFTER VACUUM
TO THE VACUUM PUMP
TO THE
REFRIGERATION
SYSTEM
TO THE CHARGE
CYLINDER
Figure 5