Repair Safety Considerations - Carrier AquaForce PUREtec 61XWHLZE 03 Installation, Operation And Maintenance Manual

1 - INTRODUCTION
System WITHOUT
No check
leakage detection
System WITH leakage
No check
detection
Refrigerant charge/
< 5
circuit (CO
2 tonnes
equivalent)
R134a charge <
(GWP 1430) 3,5 kg
R407C charge <
(GWP 1774) 2,8 kg
R410A charge <
(GWP 2088) 2,4 kg
HFO's :
R1234ze(E)
(1) From 01/01/2017, units must be equipped with a leakage detection system
• A logbook must be established for the systems that
require a tightness check. It should contain the quantity
and the type of fluid present within the installation
(added and recovered), the quantity of recycled fluid/
regenerated/destroyed, the date and output of the leak
test, the designation of the operator and its belonging
company, etc.
• Contact your local dealer or installer if you have any
questions.
PROTECTION DEVICE CHECKS:
• Periodic inspections of the safety devices and external
overpressure devices (external relief valves) must be
carried out in accordance with national regulations.
The company or organisation that conducts a pressure switch test
shall establish and implement a detailed procedure to fix:
• Safety measures
• Measuring equipment calibration
• Validating operation of protective devices
• Test protocols
• Recommissioning of the equipment.
An example of test procedure without removing the pressure switch
is given in Section 11.9 of this manual. Consult Carrier Service for
this type of test.
CAUTION: If the test leads to replacing the pressure switch,
it is necessary to recover the refrigerant charge, these
pressure switches are not installed on automatic valves
(Schraeder type).
At least once a year thoroughly inspect the protection devices
(valves). If the machine operates in a corrosive environment,
inspect the protection devices more frequently.
Regularly carry out leak tests and immediately repair any leaks
(follow local codes)
Ensure regularly that the vibration levels remain acceptable and
close to those at the initial unit start-up.
Change the refrigerant when there are equipment failures, following a
procedure such as the one described in NF E29-795 or carry out a
refrigerant analysis in a specialist laboratory.
If the refrigerant circuit remains open for longer than a day after
an intervention (such as a component replacement), the openings
must be plugged and the circuit must be charged with nitrogen
(inertia principle). The objective is to prevent penetration of
atmospheric humidity and the resulting corrosion on the internal
walls and on non-protected steel surfaces.
8
12
6 months 3 months
months
24
12 months 6 months
months
5 ≤ 5 ≤ charge charge >
charge < < 500 500
50 tonnes tonnes tonnes
3,5 ≤ 34,9 ≤
charge >
charge < charge <
349,7 kg
34,9 kg 349,7 kg
2,8 ≤ 28,2 ≤
charge >
charge < charge <
281,9 kg
28,2 kg 281,9 kg
2,4 ≤ 23,9 ≤
charge >
charge < charge <
239,5 kg
23,9 kg 239,5 kg
no requirement

1.4 - Repair safety considerations

Equip the engineers that work on the unit with the protections
described in section 1.3 above.
It is compulsory to wear personal protection equipment and a
detector of explosive atmospheres.
(1)
The insulation must be removed and warming up must be limited
by using a wet cloth.
Before opening the unit, always ensure that the circuit has been
purged.
If work on the evaporator is required, ensure that the piping from
the compressor is no longer pressurised (as the valve is not
leaktight in the compressor direction.)
All installation parts must be maintained by the personnel in charge,
in order to avoid material deterioration and injuries to people. Faults
and leaks must be repaired immediately. The authorized technician
must have the responsibility to repair the fault immediately. Each time
repairs have been carried out to the unit, the operation of the protection
devices must be re-checked.
Comply with the regulations and recommendations in unit and
HVAC installation safety standards, such as: EN-378, ISO-5149,
etc.
If a leak occurs or if the refrigerant becomes contaminated (e.g. by a
short circuit in a motor) remove the complete charge using a recovery
unit and store the refrigerant in mobile containers.
Repair the leak detected and recharge the circuit with the total
R1234ze(E) charge, as indicated on the unit name plate. Certain
parts of the circuit can be isolated. Only charge liquid refrigerant
R1234ze(E) at the liquid line.
Ensure that you are using the correct refrigerant type before
recharging the unit.
Charging any refrigerant other than the original charge type
R1234ze(E) will impair machine operation and can even lead to
a destruction of the compressors. The compressors operating with
this refrigerant type are lubricated with a specific synthetic
polyolester oil.
Do not use oxygen to purge lines or to pressurize a machine
for any purpose. Oxygen gas reacts violently with oil, grease,
and other common substances. Nitrogen should be used to
purge the system. It should also be used during brazing.
Never exceed the specified maximum operating pressures.
Verify the allowable maximum high- and low-side test
pressures by checking the instructions in this manual and
the pressures given on the unit name plate.
Do not use air for leak testing. Use only refrigerant or
dry nitrogen.
Do not unweld or flamecut the refrigerant lines or any
refrigerant circuit component until all refrigerant (liquid and
vapour) has been removed from the unit and the system has
been purged with nitrogen. Traces of vapour should be
displaced with dry air nitrogen. Refrigerant in contact with
an open flame produces toxic gases.
The necessary protection equipment must be available, and
appropriate fire extinguishers for the system and the
refrigerant type used must be within easy reach.
Do not siphon refrigerant.