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1)
The entire refrigerant has leaked
Analysis of Trouble
Leak points in the refrigerating system have not been found and repaired timely, allowing
refrigerant to leak completely. There are two kinds of leaks: slow leaks
and fast leaks. Symptoms
of total leakage of refrigerant are:
i. The compressor can be started easily (if there is no damage to the compressor parts)
ii. The operating current becomes low
iii. The gas suction pressure increases
iv. The discharge pressure decreases
v. The temperature of the gas discharge tube drops
vi. There is no sound of gas eruption from the liquid in the evaporator, and
vii. No gas gushes out of the process tube when cut after shutdown
Remedy
Check the whole machine, particularly those locations which are liable to leak. After leak points
have been found, repair them or replace them with new parts according to specific
circumstances. Then evacuate the system and finally charge refrigerant.
2) Refrigerating system is clogged with ice
Analysis of Trouble
This is typically a result of a poor dryness treatment, improper air purging, or substandard water
content. The symptoms of this condition are:
- Irregular refrigeration, extreme frosting at the clogged area,
- Evaporation temperature drops below 0°C or 32°F,
- Water accumulates and gradually clogs the narrow part of the capillary,
- Frost to melt at the evaporator, there is no sound of gas flowing,
- The gas suction pressure becomes a vacuum.
Note that these phenomena will appear intermittently. In order to know whether the system is
clogged with ice, heat the parts that are suspected with hot water. If the sound of gas flowing is
heard and the gas suction pressure rises, the trouble is that the system is clogged by ice.
