REFRIGERATION
SYSTEM
• REFRIGERATION SYSTEM
The refrigeration system consists of a hermetically sealed compressor, cold wall
evaporator and air cooled condenser.
• DRIER
The drier is installed in the system just before the capillary tube. Its purpose is to trap
minute particles of foreign material and absorb any moisture in the system.
• LIQUID CONTROL AND HEAT EXCHANGE
Liquid refrigerant control to the evaporator of the system is accomplished by the use of a
capillary tube. This capillary tube is soldered to the suction line to form a heat exchanger, which
sub cools the liquid refrigerant to maintain high efficiency within the system.
• REFRIGERATION SERVICE EVACUATION
Moisture in a refrigeration system is directly or indirectly the cause of more problems and
complaints than all other factors combined. When large amounts are present, system freeze ups
will occur. Even in minute amounts, moisture will combine with refrigerants to form an acid.
The corrosive action of this acid forms sludge which will plug the lines and the drier. Since most
field type vacuum pumps cannot pull a low enough vacuum to remove moisture from the
system, it is recommended that the system be triple evacuated, breaking each time with dry
refrigerant. Use care to purge the air from the system
• CHARGING REFRIGERATION SYSTEM
Since capillary tube systems have small critical refrigerant charges, we recommend that a field
charge either be weighed in or put in from a portable charge cylinder. After maximum vacuum
has been obtained as detailed above, attach charging cylinder to the suction line making sure to
purge air from hose with refrigerant. With the unit running, allow refrigerant to run slowly into
the system until the desired charge is reached.
OVERCHARGE:
When the cabinet has pulled down to operating temperature an indication of
an overcharge is that the suction line will be cooler than normal with the compressor running.
Running time will be higher than normal. Suction line will sweat or frost. Reclaim excessive
refrigerant from the system very carefully in small amounts waiting several minutes for the
system to balance.
UNDERCHARGE:
An undercharge or shortage of refrigerant will result in any of the
following:
1. Lower than normal head pressure.
2. Lower than normal suction pressure.
3. Excessive or continuous operation of compressor.
4. Higher than normal cabinet temperature.
