Maintenance; Components; Lubrication; Deposit - Hitachi RCUE40AG1 Installation, Operation And Maintenance Instructions

11. MAINTENANCE

The unit should be periodically inspected according to the
same items as those described in the paragraph titled
"Test Running". In order to ensure dependable
performance and long life operation, the following
additional items should be given for particular attention.
"
WARNING:
If a fire accidentally occurs, turn OFF the main switch
and use an extinguisher for an oil fire and an electric
fire.
Do not operate the unit near flammable gases such
lacquer, paint oil, etc. to avoid a fire or an explosion.
Turn OFF the main switch when electrical box covers
are removed for setting the temperature. Do not
operate the unit without fixing panels.

11.1. COMPONENTS

"
Compressor
The semi-hermetic screw compressor requires periodic
maintenance, including replacement of parts. See the
HITACHI Service Handbook for Screw Compressors, for
details.
"
Air-cooled Condenser
Inspect the condenser and remove any accumulated dirt
from the coil, at regular intervals. Other obstacles such as
growing grass and pieces of paper, which might restrict Air
flow, should also be removed.

11.2. LUBRICATION

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Compressor
The compressors are charged at the factory with the
correct oil listed in the compressor nameplate. It is not
necessary to add oil, if the refrigerant cycle remains sealed.
11.3. DEPOSITS
Lime and other minerals in the condenser water or chilled
water tend to deposit on inside surfaces of plates over a
long period of operation. As deposits of these minerals
increase, excessive power consumption, excessive high
discharge pressure or lower operation pressure are
detected, indicating evidence of deposits on the condenser
or the water cooler.
#
CAUTION:
Cleaning of plate type heat exchangers shall be
performed by specialists. Please contact your
contractor or dealer of HITACHI.
Clean the water strainer filter periodically according to
its clogging degree.
#
CAUTION:
Perform periodical maintenance according to the
"INSTRUCTIONS" to maintain the unit in a good
condition.
Do not touch the parts at the discharge gas side by
hand, since the pipes at the discharge side are
heated by refrigerant and the temperature becomes
°
higher than 100 C.
Do not utilise this unit for cooling or heating of
drinking water or food. Comply with local codes and
regulations.
Turn OFF all the main switches if refrigerant leakage
or chilled water leakage occurs. Also, if the unit can
not be stopped by the control switch, turn OFF all the
switches for power source.
"
Electrical Equipment
Always pay careful attention to working voltage, amperage
and phase balance. Check for faulty contact caused by
loosened terminal connections, oxidised contacts, foreign
matter, and others.
"
Control and Protective Devices
Do not readjust the settings in the field unless the setting is
maintained at the point other than the point listed in the
table on page 38.
"
Fan Motor
Bearing of all fan motors are pre-lubricated. Lubrication is
not required.
"
WARNING:
This product is equipped with plate type heat
exchangers. In the plate type heat exchanger, water
flows through a narrow space between plates.
Therefore, there is a possibility that freezing may
occur if foreign particles or dusts are clogged. In
order to avoid this clogging, provide a 20 mesh water
strainer at the inlet of the chilled water piping near the
product. If clogging in the plate type heat exchanger
occurs seriously, this will cause insufficient cooling
performance or local freezing in the plate type heat
exchanger. It is strongly recommended that the heat
exchanger be cleaned at the same time when the
filter is cleaned.
Pay attention to the following caution and normal
cleaning method. For details, contact your Hitachi
installer.
MAINTENANCE
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