Repair Safety Considerations - Carrier AquaSnap 61WG Series Installation, Operation And Maintenance Instructions

1 - INTRODUCTION
9. Contact your local dealer or installer if you have any
questions.
The information on operating inspections given in annex C
of standard EN378 can be used if no similar criteria exist in
the national regulations.
Protection device checks:
- If no national regulations exist, check the protection
devices on site in accordance with standard EN378: once
a year for the high-pressure switches, every five years
for external relief valves.
- The detailed description of the high-pressure switch test
method is given in the service manual for the unit.
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.
Consult your nearest service office for this type of test. Here is
mentions only the principle of a test without removing the pressure
switch:
- Verify and 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 calibrated pressure gauge (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).
- At least once a year thoroughly inspect the protection devices
(valves, pressure switches). If the machine operates in a
corrosive environment, inspect the protection devices more
frequently.
- Regularly carry out leak tests and immediately repair any
leaks.

1.4 - Repair safety considerations

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. After each repair of the unit, check the operation
of the protection devices and create a report of the parameter
operation at 100%.
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 polluted (e.g. by a
short circuit in a motor or BPHE frost) 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
R-410A charge, as indicated on the unit name plate. Do not top
up the refrigerant charge. Only charge liquid refrigerant R-410A
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
(R-410A) will impair machine operation and can even destroy
the compressors. The compressors operating with this
refrigerant type are lubricated with a synthetic polyolester oil.
For 30WGA units with remote condenser the installer must
clearly note the total refrigerant charge used in the system
(in kg) on the label attached to the 30WGA.
Before any intervention on the refrigerant circuit the complete
refrigerant charge needs to be recovered.
RISK OF EXPLOSION: Never use air or a gas containing
oxygen during leak tests to purge lines or to pressurise a
machine. Pressurised air mixtures or gases containing
oxygen can be the cause of an explosion. Oxygen reacts
violently with oil and grease.
Only use dry nitrogen for leak tests, possibly with an
appropriate tracer gas.
If the recommendations above are not observed, this can
have serious or even fatal consequences and damage the
installation.
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 unweld or flamecut the refrigerant lines or any
refrigerant circuit component until all refrigerant (liquid and
vapour) as well as the oil have been removed from unit. Traces
of vapour should be displaced with dry 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.
The accidental releases of the refrigerant, due to small leaks
or significant discharges following the rupture of a pipe or
an unexpected release from a relief valve, can cause frostbites
and burns to personnel exposed. Do not ignore such injuries.
Installers, owners and especially service engineers for these
units must:
- Seek medical attention before treating such injuries.
- Have access to a first-aid kit, especially for treating eye
injuries.
We recommend to apply standard EN 378-3 Annex 3.
Avoid spilling liquid refrigerant on skin or splashing it into
the eyes. Use safety goggles and safety gloves. Wash any
spills from the skin with soap and water. If liquid refrigerant
enters the eyes, immediately and abundantly flush the eyes
with water and consult a doctor.
Never apply an open flame or live steam to a refrigerant
container. Dangerous overpressure can result. If it is
necessary to heat refrigerant, use only warm water.
During refrigerant removal and storage operations follow
applicable regulations. These regulations, permitting
conditioning and recovery of halogenated hydrocarbons
under optimum quality conditions for the products and
optimum safety conditions for people, property and the
environment are described in standard NF E29-795.
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