LG GBB530***F Series, Service Manual

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F eatures of refrigerant (R 600a)
• Achromatic and odor less gas.
• F lammable gas and the ignition (explosion) at 494°C .
• Upper/lower explosion limit: 1.8%~8.4%/Vol.
F eatures of the R 600a refrigerator
• C harging of 60% refrigerant compared with a R 134a model.
• The suction pressure is below 1bar (abs) during the operation.
• B ecause 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.
• T he dis placement of compres s or us ing R 600a mus t be at
least 1.7 times larger than that of R 134a.
• Any type of dryer is applicable (XH-5, 7, 9).
• The E VAP OR ATOR or any other cycle part that has welding
joint is hidden in the foam. (If not hidden inside, the whole
electric pa rts mus t be tes ted with the L E AK AG E T E S T
according to the IE C S tandard.)
• The compressor has label of the refrigerant R 600a.
• Only the S VC man must have an access to the system.
After the refrigerant (R 600a) is completely discharged,
repair any defective parts and replace the dryer. At any
case you must use the LOKR ING for connecting or replacing
any part in the cycle (No Fire, No Welding). C harge the N2
gas in order to check for leakage from welding points and the
LOKR ING . If leakages are found, repair the defects again.
C onnect the S chrader 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 -1atm or -760mmHg, absolute pressure 0 ).
R ecommended vacuum time is 30 min.
After the s ys tem is completely vacuumed, fill it with the
refrigerant R 600a up to what has been s pecified at your
refrigerator Name P late. The amount of refrigerant (R 600a)
mus t be precis ely meas ured within the error of ±2g by an
electron scale (F igure 4).
If you use the manifold connected with both the refrigerant
(R 600a) cylinder and the vacuum pump simultaneously, make
sure the pump valve is closed (F igure 5).
C onne c t the c ha rging hos e ( tha t is c onne c te d to the
refrigerant (R 600a) cylinder) to the S chrader valve installed
on the service tube. Then, charge the refrigerant (R 600a) by
controlling the T hrottle valve. When you do so, do not fully
open the Throttle valve because it may make damage to the
compres s or. G radually charge the refrigerant (R 600a) 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. C lose the S chrader valve cap after the
refrigerant (R 600a) is completely recharged.
After you completely recha rge the refrigera nt (R 600a ),
perform the leakage test by using a portable leakage detector
or s oapy water. T es t the low pres s ure (s uction) parts in
compressor off time and high pressure parts in compressor
on time. If the leakages are found, restart from the refrigerant
(R 600a) discharging process and repairs defects of leaks.
After the leakage test, check the temperature of each parts of
the cycle. C heck with hands if the C ONDE NS E R and the
case (HOT -LINE pipe) that is contacted to the door gasket
are warm. C onfirm that fros t is uniform dis tributed on the
surface of the E VAP OR ATOR .
Ins tallation place
• Must be well ventilated.
• Must be 20 m
3
or larger.
• Must be no-smoking area.
• No ignitable factors must be present.
Utilities
• R efrigerant cylinder (MAX NE T 300g)
• Manometer
• Vacuum pump (600 ℓ /min)
• P iercing C lamp
• Quick coupler
• Hoses (5m-1E A, 1m-3E A)
• LOK R ING
• P ortable Leakage detector (3g/year )
• Nitrogen cylinder (for leakage test)
• C oncentration gauge
Make s ure before S ervicing
• R efrigerant
C onfirm the refrigerant by checking Name P late and the label
on the compressor, after opening the C OVE R AS S E MB LY ,
B AC K -M/C .
• If the refrigerant is R 600a, you must not weld or apply a heat
source.
Air R echarging in C ompres s or
B efore refilling the refrigerant, you mus t perform the tes t
according to C hapter 5 (TR OUB LE S HOOTING C HAR T). When
the defects a re found, you mus t dis cha rge the res idua l
re frige ra nt (R 600a ) in the outdoor. F or dis cha rging the
refrigerant R 600a, break the narrow portion of tube extension
by hand or with a pipe cutter as shown in F igure 1. Leave it for
30min in outside to stabilize the pressure with ambient. Then,
check the pres s ure 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 S chrader valve (one-
way valve) by using the LOK R ING (F igure 2). Then, connect
the S chra der va lve (one-wa y va lve) to the pump tha t is
connected to the dis charging hos e leading to the outs ide.
When discharging the residual refrigerant, repeat 3 cycle that
includes 3min of the pump running->pump off->30sec of the
compressor running.
F igure 1 F igure 2
F igure 3
F igure 4
F igure 5
S E R VIC ING P R E C AUTIONS