Daikin EWWD320, Installation, Operation And Maintenance Manual

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appropriate materials for this unit. Unsuitable maintenance can result in uncontrolled losses in pressure and fluid. Do not
disperse the refrigerant and lubricating oil in the environment. Always be equipped with a suitable recovery system.
The units ship with a full refrigerant charge, but in some cases it might be necessary to adjust the machine in the field.
ATTENTION
Always verify the causes of a loss of refrigerant. Repair the system if necessary then recharge it.
The machine can be replenished under any stable load condition (preferably between 70 and 100%) and under any
ambient temperature (preferably above 20°C), evaporator and condenser water temperature should be close (even if it is
not necessary to be exactly) at the rated conditions
Note: When the load or the cooling water temperature vary (for example due to cooling tower fans starting/stopping), so
does the subcooling and it requires several minutes to stabilise again. However, the subcooling should not come below
3°C under any condition. Also, the subcooling value can change slightly as the evaporator water temperature and the
suction superheat vary. As the suction superheating value decreases, there is a corresponding decrease in subcooling.
One of the following two scenarios can arise in a machine without refrigerant:
1. If the refrigerant level is slightly low, suction superheating is always higher than normal and the valve is wide open.
Replenish the circuit as described in the replenishment procedure.
2. If the gas level in the machine is moderately low, the corresponding circuit could have some low-pressure stops.
Replenish the corresponding circuit as described in the replenishment procedure.