11 - STANDARD MAINTENANCE
Air conditioning equipment must be maintained by profes-sional
technicians, whilst routine checks can be carried out locally by
specialised technicians. See the standard EN 378-4.
Simple preventive maintenance will allow you to get the best
performance from your HVAC unit:
• improved cooling performance
• reduced power consumption
• prevention of accidental component failure
•
prevention of major time-consuming and costly inter-
ventions
• protection of the environment
There are five maintenance levels for HVAC units, as defined by the
AFNOR X60-010 standarjd.
11.1 - Level 1 maintenance
See note below.
Simple procedure can be carried out by the user:
• Visual inspection for oil traces (sign of a refrigerant leak)
• Check for removed protection devices, and badly closed
doors/covers
• Check the unit alarm report when the unit does not work
(see report in the SmartVu
TM
control manual).
•
Check the clogging state of filters of aeration openings of
the control box.
General visual inspection for any signs of deterioration.
11.2 - Level 2 maintenance
See note opposite.
This level requires specific know-how in the electrical, hydraulic
and mechanical fields. It is possible that these skills are avail-able
locally: existence of a maintenance service, industrial site,
specialised subcontractor.
In these cases, the following maintenance operations are
recommended.
Carry out all level 1 operations, then:
• At least once a year tighten the power circuit electrical
connections (see tightening torques table).
• Check and re-tighten all control/command connections, if
required (see tightening torques table).
• Check the differential switches for correct operation every
6 months.
• Remove the dust and clean the interior of the control boxes,
if required. Check filter cleanliness (if present).
• Check the presence and the condition of the electrical
protection devices.
• Replace the fuses every 3 years or every 15000 hours
(age-hardening).
•
Replace the control box cooling fans (if used) every five
years.
• Check the water connections.
• Purge the water circuit (see chapter 7 “Water connec-tions”).
•
Clean the water filter (see chapter 7 “Water connec-tions”).
• Check the unit operating parameters and compare them
with previous values.
• Keep and maintain a maintenance sheet, attached to each
HVAC unit.
All these operations require strict observation of adequate safety
measures: individual protection garments, compliance with all
industry regulations, compliance with applicable local regulations
and using common sense.
11.3 - Level 3 (or higher) maintenance
See note below.
The maintenance at this level requires specific skills/approval/
tools and know-how and only the manufacturer, his representative
or authorised agent are permitted to carry out these operations.
These maintenance operations concern for example:
•
A major component replacement (compressor, evapo-rator)
• Any intervention on the refrigerant circuit (handling
refrigerant)
• Changing of parameters set at the factory (application
change)
• Removal or dismantling of the HVAC unit
• Any intervention due to a missed established mainte-nance
operation
• Any intervention covered by the warranty.
NOTE: Any deviation or non-observation of these mainte-nance
criteria will render the guarantee conditions for the HVAC unit
nul and void, and the manufacturer, Carrier France, will no
longer be held responsible.
11.4 - Tightening of the electrical connections
11.4.1 - Tightening torques for the main electrical
connections
Screw type
Designation
in the unit
Torque
value,
N·m
Customer connection
Screw-nut M12 at phase decks
L1/L2/L3
50
Nut on earth terminal
PE
81
Downstream power connections in the control box
Screw M10 at downstream main
disconnect deck (QS10)*
L1/L2/L3
50
Earth terminal M10
50
Power connections in the variator
GS-
M10 nut on the phase pin
19-40
M10 nut on the earth pin
19-40
Compressor phase connection terminals
M12
1/2/3/4/5/6 on EC-
23
M16
1/2/3/4/5/6 on EC-
30
Compressor earth connection
Gnd on EC-
25
Control disconnect connections
Upstream and downstream screws at
terminals
QF
2
ATTENTION: The tightening of the connections at the
compressor terminals requires special precautions. Please
refer to the chapter below.
11.4.2 - Connection precautions for the compressor
power terminals
These precautions must be applied during an intervention that
requires the removal of the power conductors connected to the
compressor supply terminals.
The tightening nut of terminal (6) supporting the isolator (7) must
never be loosened, as ist ensures terminal tightness and
compressor leak tightness.
The tightening of phase lug (4) must apply the torque between
counter nut (5) and tightening nut (3): during this operation a
counter-torque must be applied at counter nut (5). Counter-nut (5)
must not be in contact with the tightening nut of terminal (6).
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