Friedrich CP14-18-24 CP14N10, Руководство по обслуживанию и запасным частям

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RESTRICTED REFRIGERANT SYSTEM
A quick check for either condition begins at the evaporator. With
a partial restriction, there may be gurgling sounds at the metering
device entrance to the evaporator. The evaporator in a partial
restriction could be partially frosted or have an ice ball close to the
entrance of the metering device. Frost may continue on the suction
line back to the compressor.
Often a partial restriction of any type can be found by feel, as
there is a temperature difference from one side of the restriction
to the other.
With a complete restriction, there will be no sound at the metering
device entrance. An amperage check of the compressor with a
partial restriction may show normal current when compared to the
unit specifi cation. With a complete restriction the current drawn may
be considerably less than normal, as the compressor is running
in a deep vacuum (no load). Much of the area of the condenser
will be relatively cool since most or all of the liquid refrigerant will
be stored there.
The following conditions are based primar ily on a system in the
cooling mode.
Troubleshooting a restricted refrigerant system can be
diffi cult. The following proce dures are the more common
problems and solutions to these problems. There are two
types of refrigerant restrictions: Partial restrictions and
complete restrictions.
• A partial restriction allows some of the refrigerant to circulate
through the system.
• With a complete restriction there is no circulation of refrigerant
in the system.
• Restricted refrigerant systems display the same symptoms as
a “low-charge condition.”
• When the unit is shut off, the gauges may equal ize very
slowly.
• Gauges connected to a completely re stricted system will run
in a deep vacuum. When the unit is shut off, the gauges will
not equalize at all.
Refrigerant Charging