Winter Shutdown; Spring Start-Up; Part Replacement - Hitachi RCUE40AG1 Installation, Operation And Maintenance Instructions

MAINTENANCE
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11.5. WINTER SHUTDOWN

When shutting down the unit for winter, clean the inside
and outside of the cabinet, and dry the unit. Pump down
the refrigerant to the condenser and close the liquid outlet
stop valves. This unit should be covered during shutdown,
in order to protect it from dust and environmental
conditions. Be sure to tighten the packing glands and the
cap nuts of the valves.

11.6. SPRING START-UP

After any extended shutdown period, prepare the unit for
operation as follows.
1. Thoroughly inspect and clean the unit.
2. Clean the water piping lines and the strainer.
Inspect the pump and other auxiliary equipment in the
piping line.
3. Tighten all wiring connections and access panel.

11.7. PART REPLACEMENT

Replacement of parts should be undertaken by ordering
from the HITACHI Spare Parts List.
11.8. REFRIGERATION CYCLE
"
Strainer
Check for clogging each time when the refrigeration cycle
is opened.
"
Refrigerant Charge
Inspect the refrigerant charge of the system by checking
the discharge and suction pressures. Perform a leakage
test, if any leakage is suspected, and always perform such
a test after a refrigeration cycle component is replaced.
When refrigerant charge is required, follow the following
instructions given for two cases:
1. When Refrigerant Gas Completely Leaked.
Before charging the entire cycle must be completely
evacuated and dehydrated. A gauge manifold or
equivalent piping preparation shown in the next page is
recommended as a convenient procedure regarding
both charging and evacuation.
! Fully open all the stop valves.
! Connect the evacuation line to the check joints of the
high and the low pressure sides.
! Completely evacuate the entire cycle with a vacuum
pump.
! Charge refrigerant to the refrigeration cycle by
weighing the charging cylinder. The proper refrigerant
charge is listed on the nameplate.
! When charging by weight is stopped due to high
ambient temperature, close the valve and operate the
unit after circulating the chilled water through the water
cooler and installing a jumper on the low pressure
switch, if required.
Remove the drain plug and drain all residual water from the
water cooler piping systems, as such water may freeze
during the cold season. It is very helpful to supply brine
(anti-freezer) to the piping systems.
#
CAUTION:
When the main switch for this unit has been at the
OFF position for an extended period of time, it should
be switched ON at least 12 hours before start-up, so
that oil in the compressor discharge casing may be
warmed enough, to prevent oil foaming by the oil
heater during start-up.
#
CAUTION:
Do not replace with spare parts which are not the
equivalent.
2. When Only Additional Refrigerant is Required.
Connect a gauge manifold to check joint of low pressure
side, and connect a charge cylinder to gauge manifold.
Operate the unit after circulating the chilled water and
install a jumper on the low pressure switch, if required.
Repeat the following procedure until pressure becomes
proper (refer to page 23).
! Charge the gas refrigerant a little slowly into
refrigeration cycle from check joint for low pressure.
! Check the pressure after refrigeration cycle becomes
stable.