38
14.9 - Electrical maintenance
When working on the unit comply with all safety precau-tions
described in section 1.3.
It is strongly recommended to change the unit fuses every
15000 operating hours or every three years.
It is recommended to verify that all electrical connections are
tight:
•
after the unit has been received at the moment of
installation and before the first start-up,
•
one month after the first start-up,when the electrical
components have reached their nominal operating
temperatures,
•
then regularly once a year.
14.10 - Tightening torques for the main electrical
connections
Component
Designation in
the unit
Value (N.m)
Screw (PE) customer connection M8
PE
14.5
Screw on switch inlet zones
Switch - MG 28904
QS_
8
Tunnel terminal screw, compressor contactor
Contactor LC1D12B7
KM*
1.7
Contactor LC1D18B7
KM*
1.7
Contactor LC1D25B7
KM*
2.5
Tunnel terminal screw, compressor circuit breaker
Circuit breaker 25507
QM*
3.6
Circuit breaker 25508
QM*
3.6
Circuit breaker 25509
QM*
3.6
Tunnel terminal screw, control power transformer
Transformer - ABL6TS16B
TC
0.6
Compressor earth terminal in the power wiring control box
M6
Gnd
5.5
Compressor earth connection
M8
Gnd
2.83
Tunnel terminal screw, pump disconnect switch
Disconnect switch GV2ME08
QM_
1.7
Disconnect switch GV2ME10
QM_
1.7
Tunnel terminal screw, pump contactor
Contactor LC1K0610B7
KM
0.8 to 1.3
Contactor LC1K09004B7
KM
0.8 to 1.3
Contactor LC1K0910B7
KM
0.8 to 1.3
Contactor LC1K0901B7
KM
0.8 to 1.3
Variable-frequency switch ATV21
GS
1.3
14.11 - Tightening torques for the main bolts and screws
Screw type
Used for
Torque (N.m)
M8 nut
BPHE* fixing
15
M10 nut
Compressor mounting
30
Oil nut
Oil equalisation line
90
Taptite screw M6
Panel fixing
7
H M6 screw
Stauff clamps
10
* BPHE = Brazed plate heat exchanger
14.12 - Compressors
The compressors do not require any specific maintenance.
Nevertheless the preventive system maintenance operations
prevent specific compressor problems. The following periodic
preventive maintenance checks are strongly recommended:
•
Check the operating conditions (evaporating tempera-ture,
condensing temperature, discharge temperature, heat
exchanger temperature difference, superheat, subcooling).
These operating parameters must always be within the
compressor operating range.
•
Check that the safety devices are all operational and
correctly controlled.
•
Check oil level and quality. If there is a colour change in the
sight glass, check the oil quality. This may include an
acidity test, moisture control, a spectrometric analysis etc
•
Check the leak tightness of the refrigerant circuit.
•
Check the compressor motor power input, as well as the
voltage imbalance between phases.
•
Check the tightening of all electrical connections.
•
Ensure that the compressor is clean and runs correctly;
verify that there is no rust on the compressor shell and no
corrosion or oxydation at the electrical connections and the
piping.
ATTENTION: The compressor and piping surface tempe-
ratures can in certain cases exceed 100°C and cause burns.
Particular caution is required during maintenance opera-
tions. At the same time, when the compressor is in operation, the
surface temperatures can also be very cold (down to -15°C for
units with a low leaving water temperature), and can cause
frost burns.
14.13 - Evaporator and condenser maintenance
There is no particular maintenance necessary on the plate heat
exchanger. Check:
•
that the insulating foam has not become detached or
damaged during work on the units,
• that the entering and leaving water temperature sensors
are well connected
•
the cleanliness on the water heat exchanger side (no signs
of leaks).
•
that the periodic inspections required by local regu-lations
have been carried out.
14.14 - Corrosion check
All metallic parts of the unit (chassis, casing panels, control
boxes, heat exchangers etc.) are protected against corrosion by a
coating of powder or liquid paint. To prevent the risk of
blistering corrosion that can appear when moisture penetrates
under the protective coatings, it is necessary to carry out
periodic checks of the coating (paint) condition.
Содержание BW10 020-090
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