Service
Operation & Maintenance Manual 53
Refrigerant Cycle
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Leakage test
As described in the installation manual, the unit is sufficiently charged with R134a refrigerant as factory setting. If the
refrigerant pressure is lower than the factory setting, you must check for leakage. If the pressure inside the unit has
dropped, use the Nitrogen to do a leakage test. When repairing the leaking part, you must use good refrigeration prac-
tice. After the leakage is repaired, any water inside the chiller must be removed and vacuumed.
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Charging the refrigerant
Insert the coupling to the refrigerant charging port. In order to avoid the damage to the tube from residual water freezing
within the evaporator, circulate the water in the evaporator (EVA) while charging the refrigerant to the designated
amount. For the amount of refrigerant to charge, refer to the installation manual or PDB.
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Charging the oil
Insert the coupling in the oil port. Check whether the oil level is above in the Sight Glass window. Remove the coupling
and insert the oil port cap. After inserting the oil, operate the product and check whether the oil level is above with the
naked eye. If not, supplement the oil.
