Refrigerant Safety Considerations - Carrier 30RBM 160 Installation, Operation And Maintenance Instructions

Provide a drain in vent line, close to each relief valve, to avoid
an accumulation of condensate or rain water.
It is recommended to install an indicating device to check
whether some of the fluid has leaked from the relief valve.
The presence of oil at the outlet orifice is a useful indicator
that refrigerant has leaked. Keep this orifice clean to ensure
that any leaks are obvious. The calibration of a valve that has
leaked is generally lower than its original calibration. The new
calibration may affect the operating range. To avoid nuisance
tripping or leaks, replace or re-calibrate the valve.
Protective device checks:
If no national regulations exist, check the protective 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,
• Values and tolerances for cut-off and discharge devices,
• Test stages,
• Recommissioning of the equipment.
The principle for performing a test without disassembly of the
pressure switch is given here, however the manufacturer
recommends contacting the Service for this type of test:
• Verify and record the set-points of pressure switches and
external 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
overpressure or excess gas if there are valves on the high
pressure side on the recovery air-cooled exchangers, for
example),
• Connect a calibrated pressure differential gauge with
integral damping (oil bath with pointer if mechanical);
instantaneous reading gauges may give inaccurate
readings because of the control's scanning delay,
• Carry out the HP quicktest built into the control (refer
to the Service Guide).
If the test results in the replacement of the pressure
switch, it is necessary to recover the refrigerant
charge; these pressure switches are not installed on
Schrader type automatic valves.
If the unit operates in a corrosive atmosphere, inspect the
devices more frequently.
Do not attempt to repair or recondition a valve if there has
been any corrosion or build-up of foreign material (rust, dirt,
scale, etc.) on the valve body or mechanism. In this case, it
must be replaced.
Do not install relief valves in series or backwards.

1.2 - Refrigerant safety considerations

Use safety goggles and safety gloves.
All precautions concerning handling of refrigerant must be
observed in accordance with local regulations.
If a leak occurs or if the refrigerant becomes contaminated
(e.g by a motor short circuit or BPHE freeze-up), and before
any intervention, remove the complete charge using a recovery
unit and store the refrigerant in mobile containers. The
compressors cannot transfer the whole refrigerant charge and
can be damaged if used to pump-down. The refrigerant charge
should not be transferred to the high-pressure side.
Repair the leak, detect and check the type of refrigerant in
the unit and then recharge the unit/circuit with the total charge,
as indicated on the unit nameplate. Do not top up the
refrigerant charge. Only charge the liquid refrigerant given on
the nameplate at the liquid line.
Charging any refrigerant other than the original type will
impair unit operation and can even cause irreparable damage
to the compressors. The compressors operating with this
refrigerant type are lubricated with a synthetic polyolester oil.
Do not unweld the refrigerant ductwork or any refrigerant circuit
component or cut these with a torch until all refrigerant (liquid
and vapour) as well as the oil have been removed from the unit.
Traces of vapour should be displaced with dry air nitrogen.
Refrigerant in contact with an open flame produces toxic gases.
Do not siphon refrigerant.
Any accidental release of refrigerant, whether this is caused by
a small leak or significant discharges following the rupture of
a pipe or an unexpected release from a relief valve, may cause
any personnel exposed to experience heart palpitations,
faintness, frostbite and burns. Always take any such event
seriously.
Installers, owners and especially service engineers for these
units must:
• Create a procedure to ensure medical attention is sought
before treating any symptoms;
• Provide first aid equipment, flush the eyes and skin
immediately if splashed with refrigerant, and seek medical
attention.
We recommend applying standard EN 378-3 Appendix 3.
Ensure there is sufficient ventilation if the unit is installed in
an enclosed area. In gas form, refrigerant is heavier than air
and, if allowed to accumulate in a confined area, it can reduce
the quantity of oxygen in the air, causing respiratory issues.
The refrigerant used in units in this range is R410A, a high-
pressure fluid (the operating pressure of the unit is greater
than 40 bar).
Special equipment must be used when working on the
refrigerating circuit (pressure gauge, charge transfer
equipment, etc.).
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