Maintenance Work - Hitachi RAS-2-HVNP Service Manual

12. Maintenance notes

12.2 Maintenance work

For the indoor unit and the outdoor unit
1 Fan and fan motor
• Lubrication: All the fan motors are pre-lubricated 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.
• Insulation: Check the electrical insulation resistance.
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 from the outdoor units 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.
4 Cabinet
• Stain and lubrication: Check for any stain and any lubrication. Remove the stain and the lubrication.
• Fixing screw: Check for any loosened screw or any lost screw. Fix the loosened screws and the lost screws. Insu-
lation 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 the section
For the outdoor 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
• Activation: You should activate the oil heater at least twelve hours before the start-up by turning ON the main
switch.
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SMGB0079 rev.0 - 01/2013
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