7. MAINTENANCE
91
7-2. Periodic inspection
Daily inspection
Evaporator pressure, condenser pressure, oil tank pressure, differential oil pressure and oil discharge pressure of the
chiller are checked.
The values are compared with the ones provided in the general chiller operation characteristics table.
- Daily inspection criteria for compressor
Classification
Inspection items
Inspection method
Standard
Compressor
Compressor discharge gas tempera-
ture
Check temperature at the control
panel
40 °C ~ 90 °C
Vibration/noise
Check with hand and ears.
If necessary, the vibration is measured with vibration meter,
Refer to the specifications for noise
If there is no abnormal vibration, the vibration should be x, y,
z : 25um or less.
* Cooling method for the motor takes the liquid refrigerant cooling method, where refrigerant is supplied to the
motor by the differential pressure between condensing pressure and evaporating pressure.
* Check whether the color of the moisture indicator in the refrigerant supply line is green.
If green changes to yellow, it shows that the moisture amount in the machine is above the permitted limit, so re-
place the filter drier.
Figure 57 Compressor daily inspection standard
ENGLISH
- Condenser daily inspection standard
If cooling water outlet temperature becomes lower than 21°C, the condensing pressure decreases making the pres-
sure difference required for motor cooling not enough, and accordingly the amount of cooling refrigerant will become
insufficient.
The biggest reason for the worsened heat exchanging would be the scale attached to inside of the cooling pipe thus
resulting in insufficient amount of cooling water.
Figure 58 Condenser daily inspection standard
Classification
Inspection items
Inspection method
Standard
Condenser
Cooling water
Inlet
Check in the panel
34°C or lower
Outlet
Check in the panel
21°C or higher
Condensing pressure
Check in the panel
6~10 kg/cm²(R134a)
8 ~ 16 kg/cm²(R22)
Heat exchanging status
Difference between condensing
temperature and coolant outlet
temperature
0.5~3°C
Summary of Contents for LCWW
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