30
9 - MajOR sysTeM COMPONeNTs aND OPeRaTION
daTa
9.1 - compressor
30XAV-ZE units use 06T geared twin-screw compressors
equipped with a variable capacity slide valve and
controlled by variable frequency drive.
Compressor capacity control is by speed variation and
then slide valve modulation.
The combination of these two control modes permits fine
control of the unit capacity between 10% and 100%.
ATTENTION: Depending on operating conditions, unit
might have a different minimum capacity or cycle.
9.2 - Oil filter
The 06T screw compressor has an independent oil filter
attached to the oil separator. This filter is field replaceable.
9.3 - refrigerant
The 30XAV-ZE water chiller operates only with
refrigerant R1234ze(E).
9.4 - lubricant
The 06T screw compressor is approved for use with the
following lubricants:
•
Carrier material specification PP47-38
ATTENTION: Too much oil in the circuit can cause a
failure.
9.5 - oil supply solenoid valve
An oil supply solenoid valve is installed on the oil return
line as standard to isolate the compressor from oil flow
when the compressor is not operating. The oil solenoid
valve is field replaceable.
9.6 - suction and economiser screens
To increase the reliability of the compressor, a screen has
been incorporated as a standard feature into suction and
economiser inlets of the compressor.
9.7 - Pressure vessels
9.7.1 - general
Observe the following guidelines during operation, testing
and certification:
•
Follow the regulations on monitoring pressurised
equipment.
•
It is normally required that the user or operator sets
up and maintains a monitoring and maintenance file.
•
If there are no regulations or to complement them
follow the guidance programmes of EN 378.
•
If they exist follow local professional recommendations.
•
Regularly inspect the condition of the coating (paint)
to detect blistering resulting from corrosion. To do this,
check a non-insulated section of the vessel or joint in
the insulation.
•
Regularly check for possible presence of impurities
(e.g. silicon grains) in the heat exchange fluids. These
impurities may cause erosion and/or corrosion.
•
Install appropriate filtration in the chilled fluid circuit.
Carry out internal inspections as described in EN 378-
2 Annexe C.
•
In case of re-testing please refer to the maximum
operating pressure given on the unit nameplate.
•
The reports of periodical checks by the user or operator
must be included in the supervision and maintenance
file.
9.7.2 - Repair
Any repair or modification, including the replacement of
parts:
•
Must follow local regulations and be made by qualified
operators and in accordance with qualified procedures,
this include changing the heat exchanger tubes.
•
Must be made in accordance with the instructions of
the original manufacturer. Repair and modification
that necessitate permanent assembly (soldering,
welding, expanding, etc.) must be made using the
correct procedures and by qualified operators.
•
An indication of any modification or repair must be
shown in the monitoring and maintenance file.
9.7.3 - Recycling
The unit is wholly or partly recyclable. After use it contains
refrigerant vapours and oil residue. It is coated with paint.
9.7.4 - operating life
This unit is designed for:
•
Prolonged storage of 15 years under nitrogen charge
with a temperature difference of 20 K per day.
•
452000 cycles (start-ups) with a maximum difference
of 6 K between two neighbouring points in the vessel,
based on 6 start-ups per hour over 15 years at a usage
rate of 57%.
