Hitachi RASC-10HNPE, Руководство по обслуживанию, Страница: 297 / 306

11 Maintenance notes
Maintenance work
SMGB0091 rev.2 - 11/2015 287
11
11.2 Maintenance work
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C A U T I O N
• All inspections and checks of the RASC unit have to be carried out by a licensed technician and never by the user itself.
• Before any inspection and checking procedure, the unit main power supply has to be switched OFF.
• Wait minimum 10 minutes or more from all power supply have been turned OFF.
• Take care with the crankcase heater. It could operate even when compressor is OFF.
• Take care with the electrical box components. Some of them could remain hot after switch OFF the unit.
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N O T E
All these maintenance operations must be done with appropriate materials and following this manual.
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For the indoor unit and RASC unit
1 Fan and fan motor
- Lubrication: All the fan motors are prelubricated and sealed at the factory. Therefore, no lubrication maintenance
is required.
- Sound and vibration: Check for abnormal sounds and vibrations.
- Rotation: Check the clockwise rotation and the rotating speed.
- Wiring: Check that the wiring is at optimum conditions and correctly tightened with its corresponding clamps.
2 Heat exchanger
- Clog: Inspect the heat exchanger at regular intervals and remove any accumulated dirt and any accumulated dust
from the heat exchanger. You should also remove other obstacles such as the growing grass and the pieces of
paper which might restrict the airflow.
3 Piping connection
- Leakage: Check for the refrigerant leakage at the piping connection between the RASC and the indoor unit.
4 Cabinet
-
Stain: Check for any stain and remove it cleaning if it is the case.
- Fixing screw: Check for any loosened screw or any lost screw. Fix the loosened screws and the lost screws.
- Insulation material: Check for any peeled thermal insulator on the cabinet. Repair the thermal insulator.
5 Electrical equipment
-
Activation: Check for an abnormal activation of the magnetic contactor, the auxiliary relay, the PCB and others.
- Line condition: Pay attention to the working voltage, the working amperage and the working phase balance.
Check for any faulty contact that is caused by the loosened terminal connections, the oxidized contacts, the
foreign matter, and other items. Check the electrical insulation resistance.
6 Control device and protection device
- Setting: Do not readjust the setting in the field unless the setting is maintained at a point that is different from the
point listed in section “5.2 Safety protection and control” on chapter “5. Control system” .
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For RASC unit
1 Compressor
- Sound and vibration: Check for abnormal sounds and vibrations.
- Activation: Check that the voltage drop of the power supply line is within 15% at the start and within 2% during the
operation.
2 Reverse valve
- Activation: Check for any abnormal activation sound.
3 Strainer
- Clog: Check that there is no temperature difference between both ends.
4 Ground wire
- Ground line: Check for the continuity to earth.
5 Oil heater (Crankcase heater)
- Activation: You should activate the oil heater at least twelve hours before the start-up by turning ON the main
switch.