Electrolux Side by Side Refrigerators, Руководство по обслуживанию

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If a slight undercharge of refrigerant is indicated and no
leak can be found after a thorough leak test, the charge
can be corrected without changing the compressor.
If a high side leak is located and some refrigerant
remains in the system it is not necessary to change the
compressor.
TESTING FOR REFRIGERANT LEAKS
If the system is diagnosed as short of refrigerant and the
system has not been recently opened there is probably
a leak in the system. Adding refrigerant without first
locating and repairing the leak or replacing the compo-
nent will not permanently correct the difficulty. The leak
must be found. Sufficient refrigerant may have es-
caped to make it impossible to leak test effectively. In
such cases, add a ¼” line piercing valve to the compres-
sor process tube. Add sufficient refrigerant vapor to
increase the pressure to 40 to 50 lb. per sq. in. Check the
low side for leaks. Run the compressor 2 or 3 minutes
and check the high side for leaks. Recover refrigerant
using an EPA approved recovery system.
NOTE: The line piercing valve (clamp-on type)
should be used for test purposes only. It must be
removed from system after it has served its purpose.
CHECKING FOR INTERNAL (HOT TUBE) LEAKS
Before checking for internal leaks, check all accessible
system components and joints for leaks.
If an internal hot tube leak is suspected, it must be
confirmed. Use the following procedure:
1. Recover refrigerant by using EPA approved recovery
system.
2. After system refrigerant is completely recovered,
disconnect drier from hot tube. Pinch off and sol-
der end of hot tube closed.
3. Cut line from condenser to hot tube and solder a
¼”charging hose fitting to open end of hot tube or
put compression fitting on tube.
4. Connect pressure gauge and access valve to hot
tube and pressurize to 250 psig using dry nitrogen
or carbon dioxide.
WARNING: NEVER PRESSURIZE WITH
OXYGEN. NEVER OPEN A HIGH PRESSURE
TANK UNLESS IT IS EQUIPPED WITH A
PRESSURE REGULATOR. NEVER PUT HIGH
PRESSURE ON DOME OF COMPRESSOR – IT
COULD EXPLODE. MAKE SURE GAUGE,
HOSES, AND ALL FITTINGS ARE IN GOOD
CONDITION AND DO NOT LEAK.
5. Leave pressure on hot tube for 24 hours. Any
drop in pressure is indication of leak.
If dry nitrogen or carbon dioxide is not available,
follow steps 1 through 3 above, then steps 4 and 5
below:
4. Connect gauges to charging hose fittings. Pull
vacuum on hot tube.
5. Leave vacuum on each side of system for 24 hours.
Any loss of vacuum indicates leak.
COMPRESSOR REPLACEMENT
CAUTION: NEVER install a new compressor
without first checking for possible system
contamination.
To check for contamination, obtain oil sample from old
compressor.
• If the oil has burned odor, but no color change or
residue — follow instructions in section “Installing A
New Compressor on page 32”.
• If oil has a burned odor and a sugar or gritty feel as
well as showing signs of contamination (dark color)
— follow instructions in next section, To Flush The
System. Remove as much of contamination as pos
sible from system before installing new compressor
and filter-drier.
To Flush The System
NOTE: It is recommended that system be flushed
with dry Nitrogen. However, if refrigerant is used to
flush the system, you must look at the serial plate
to see what type of refrigerant is used in the
system. This is the only refrigerant that can be
used to flush the system and it must be recovered.
CAUTION: Use extreme care when using Dry
Nitrogen to flush systems. Pressure in nitrogen
cylinder could be as high as 2000 psi. Nitrogen
cylinder must be equipped with approved
pressure regulator and pressure relief valve.
Ensure that your hoses have adequate ratings
for pressure involved and that all of your
equipment is in good condition.
CAUTION: The end of the flushing hose on the
tank regulator must be equipped with a hand
shut-off valve (Robinair No. 40380). Close hand
shut-off valve and adjust nitrogen regulator to
correct pressure before proceeding with flushing
procedure.