6
Any manipulation (opening or closing) of a shut-off valve must
be carried out by a qualified and authorised engineer. These
procedures must be carried out with the unit shut-down.
NOTE: The unit must never be left shut down with the liquid
line valve closed, as liquid refrigerant can be trapped between
this valve and the expansion device and lead to the risk of a
pressure increase. This valve is situated on the liquid line
before the filter drier box.
Equip the engineers that work on the unit as follows:
Personal protection
equipment (PPE)
(1)
Operations
Handling
Maintenance,
service
Welding or
brazing
(2)
Protective gloves,
eye protection,
safety shoe,
protective clothing.
X
X
X
Ear protection.
X
X
Filtering respirator.
X
(1) We recommend to follow the instructions in EN 378-3.
(2) Performed in the presence of A1 refrigerant according to EN 378-1.
Never work on a unit that is still energized.
Never work on any of the electrical components, until the
general power supply to the unit has been cut using the
disconnect switch(es) in the control box(es).
If any maintenance operations are carried out on the unit,
lock the power supply circuit in the open position ahead of
the machine.
If the work is interrupted, always ensure that all circuits are
still deenergized before resuming the work.
ATTENTION: Even if the unit has been switched off, the power
circuit remains energized, unless the unit or circuit disconnect
switch is open. Refer to the wiring diagram for further details.
Attach appropriate safety labels.
Units with option 231 are equipped with capacitor batteries
with a discharge time of five (5) minutes after disconnecting
the power. After disconnecting the power to the control box,
wait five minutes before opening the control box. Before any
intervention, verify that there is no voltage present at any
accessible conducting parts of the power circuit.
Operating checks:
Important information regarding the refrigerant used:
-
It’s a HFO gas.
Fluid type: R1234ze(E)
Global Warming Potential (GWP): 1 (following AR5)
CAUTION:
1. Ensure that the refrigerant is never released to the
atmosphere during installation, maintenance or equipment
disposal.
2. The deliberate gas release into the atmosphere is not
allowed.
3. If a refrigerant leak is detected, ensure that it is stopped
and repaired as quickly as possible.
4. Only a qualified and certified personnel can perform
installation operations, maintenance, refrigerant circuit
leak test as well as the equipment disposal and the
refrigerant recovering.
5. The gas recovery for recycling, regeneration or destruction
is at customer charge.
6. Periodic leak tests have to be carried out by the customer
or by third parties. The EU regulation set the periodicity
here after:
System WITHOUT leakage
detection
No
check
12
months
6
months
3
months
System WITH leakage
detection
No
check
24
months
12
months
6
months
Refrigerant charge/circuit
(CO
2
equivalent)
< 5
tons
5 ≤
charge <
50 tons
50 ≤
charge <
500 tons
Charge >
500
tons
(1)
Refrigerant
charge/circuit
(kg)
R1234ze(E)
(GWP 1)
No requirement
(1) From 01/01/2017, units must be equipped with a leakage detection system
7. A logbook must be established for equipments subject to
periodic leak tests. It should contain the quantity and the
type of fluid present within the installation (added and
recovered), the quantity of recycled fluid, regenerated or
destroyed, the date and output of the leak test, the
designation of the operator and its belonging company,
etc.
8. Contact your local dealer or installer if you have any
questions.
The information on operating inspections given in annex C
of standard EN 378 can be used if no similar criteria exist in
the national regulations.
While working in the fan area, especially when grilles or
casings are removed, disconnect the fan power supply to
prevent their automatic restart.
PROTECTION DEVICE CHECKS:
-
If no national regulations exist, check the protection
devices on site in accordance with standard EN 378:
Once a year for the high-pressure switches, every five
years for external relief valves.
The company or organisation that conducts a pressure switch test
must establish and implement detailed procedures for:
-
Safety measures
-
Measuring equipment calibration
-
Validating operation of protective devices
-
Test protocols
-
Recommissioning of the equipment.
Consult Carrier Service for this type of test. Carrier mentions here
only the principle of a test without removing the pressure switch:
-
Verify and record the set-points of pressure switches and
relief devices (valves and possible rupture discs)
-
Be ready to switch-off the main disconnect switch of the power
supply if the pressure switch does not trigger (avoid over-
pressure or excess gas in case of valves on the high-pressure
side with the recovery condensers)
-
Connect a pressure gauge protected against pulsations (filled
with oil with maximum pointer if mechanical), preferably
calibrated (the values displayed on the user interface may
be inaccurate in an instant reading because of the scanning
delay applied in the control)
-
Complete an HP Test as provided by the software (refer to
the Control IOM for details).
If the machine operates in a corrosive environment, inspect
the protection devices more frequently.
Regularly carry out leak tests and immediately repair any
leaks. Ensure regularly that the vibration levels remain
acceptable and close to those at the initial unit start-up.
Before opening a refrigerant circuit, purge and consult the
pressure gauges.
Change the refrigerant after an equipment failure, following
a procedure such as the one described in NF E29-795 or carry
out a refrigerant analysis in a specialist laboratory.
Plug all openings whenever the refrigerant circuit is opened
for up to one day. For longer openings place a nitrogen charge
in the circuit.
1 - INTRODUCTION
