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Remedy
If there is too much moisture in the refrigerating system, release the refrigerant, purge the tubing
with nitrogen, and then refill the system with the filtered refrigerant. Another method is to
connect a filter with moisture absorbers, such as silica gel or anhydrous calcium chloride, to the
refrigerating system. Next, replace the filter, evacuate it again, and fill the system with
refrigerant.
3) Refrigerating system is clogged with dirt
Analysis of Trouble
Coarse-grained dirt and refrigerant oil in the system tend to settle and clog the capillary inlet.
Flow of refrigerant stops when the filter screen is completely clogged by dirt. This condition has
the same symptoms as when the refrigerating system is clogged by ice. However, when you heat
the clogged area with a hot towel, there is no reaction. After rejecting the possibility of ice
clogging, it can be concluded that the clogging is due to dirt.
Remedy
Dismantle the system. Remove the dry filter and purge the tubing with nitrogen. Next, install a
new filter. Then evacuate it and fill with refrigerant.
4) Clogged filter
Analysis of Trouble
The complete clogging of the filter rarely occurs. Oftentimes, there is an accumulation of paste-
like matter formed from dust on the filter. Tapping the filter may remove part of the paste-like
matter. When the filter is clogged, it will be cooler than normal.
Remedy
The same as described for the capillary clogged with dirt.
•
Troubles of Compressor
1) Broken gas suction and discharge valve blocks
Analysis of Trouble
The compressor works by opening and closing the gas suction valve and discharge valve to suck
and discharge the refrigerant. If the valve block is broken, the refrigerant cannot be discharged.
This prevents refrigeration.
Remedy
It is quite difficult to differentiate this trouble from others because they have similar symptoms.
When repairing, listen attentively for abnormal sounds coming from the compressor. Oftentimes,
broken pieces of valve block strike against the cylinder. Check to see if the compressor casing is
too hot. Secondly, measure the pressures at the high and low-pressure ports of the compressor
