Electrolux Wine Cooler / Beverage Center, Service Manual

Page: 20 / 44

20
D - Refrigeration System
NOTICE
Instructions given here are furnished as a guide.
Persons attempting to use these instructions to
make repairs to the sealed refrigeration system
should have a working knowledge of refrigeration
and previous training on sealed system repair,
and an EPA certification for servicing refrigeration
systems.
IMPORTANT NOTICE
Effective July 1, 1992, the United States clean
air act governs the disposal of refrigerants such
as R-134a. Therefore, when discharging or
purging the sealed system use an epa approved
refrigerant recovery system as outlined in the final
rule on the protection of stratospheric ozone and
refrigerant recycling, which was published in the
Federal Register May 14, 1993.
NOTE
Frigidaire does not permit the use of recovered
refrigerant in the servicing of our products for
in-warranty and out-of-warranty repairs or for
products covered by service contracts. Therefore,
only new refrigerant or refrigerant that has
been reclaimed back to new specifications by a
refrigerant manufacturer is to be used.
Definitions
Recovery:
To remove refrigerant in any condition from a
system and store it in an external container without
necessarily testing or processing it in any way.
Recycling:
To clean refrigerant for reuse by oil separation and
single or multiple passes through devices, such
as replaceable core filter-driers, which reduce
moisture, acidity and particulate matter. This term
usually applies to procedures implemented at the
field job site or at a local service shop.
Reclaim:
To reprocess refrigerant to new product
specifications by means which may include
distillation. Will require chemical analysis of the
refrigerant to determine that appropriate product
specifications are met. This term usually implies the
use of processes or procedures available only at a
reprocessing or manufacturing facility.
Safety Warnings
Compressor Testing
Whenever testing a compressor, extreme caution
should be used to prevent damaging the terminals.
A compressor with a damaged terminal or a
grounded winding can expel a terminal from
its insulated housing when the compressor is
energized. If this happens, a mixture of refrigerant
and oil will be released that could be ignited by
an external heat source (open flame, heater,
etc.). Also, if there is air in the system when this
happens, a spark at the compressor shell could
ignite the refrigerant and oil mixture.
Charging Sealed Systems
Overcharging a refrigeration system with refrigerant
can be dangerous. If the overcharge is sufficient
to immerse the major parts of the motor and
compressor in liquid refrigerant, a situation has
been created which, when followed by a sequence
of circumstances can lead to the compressor shell
seam separating.
A hydraulic block occurs, preventing the
compressor from starting. This condition is known
as locked rotor. Electric current continues to flow
through the compressor motor windings which
become, in effect, electric resistance heaters.
The heat produced begins to vaporize the excess
refrigerant liquid causing a rapid increase in
system pressure. If the compressor protective
devices fail, the pressure within the system may
rise to extremes far in excess of the design limits.
Under these conditions, the weld seam around
the compressor shell can separate with explosive
force, spewing oil and refrigerant vapor which could
ignite.
To eliminate this exceedingly rare but potential
hazard, never add refrigerant to a sealed system. If
refrigerant is required, evacuate the existing charge
and recharge with the correct measured amount of
the refrigerant specified for the system.