Maintenance Safety Considerations; Repair Safety Considerations - Danfoss BW05 Installation, Operation And Maintenance Instructions

1.3 - Maintenance safety considerations

Engineers working on the electric or refrigeration compo-
nents must be authorized, trained and fully qualified to do so.
All refrigerant circuit repairs must be carried out by a trained
person that is familiar with the equipment and the
installation, and fully qualified to work on these units. All
welding operations must be carried out by qualified
specialists.
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.
ATTENTION: The liquid line valve must always be fully open,
when there is refrigerant in the circuit (this valve is situated
on the liquid line before the filter drier box.
Any intervention on the refrigerant circuit, including chang-
ing of drier blocks, is only permitted after the complete
removal of the refrigerant charge. For these units transfer
of the refrigerant charge from the high or low-pressure side
is not possible, nor permitted.
During any handling, maintenance and service operations
the engineers working on the unit must be equipped with
safety gloves, glasses, shoes and protective clothing.
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 in the control box.
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 compressor motors have 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.
Operating checks:
IMPORTANT INFORMATION REGARDING THE
REFRIGERANT USED:
• This product contains fluorinated greenhouse gas
covered by the Kyoto protocol.
Refrigerant type: R-407C
Global Warming Potential (GWP): 1653
Periodic inspections for refrigerant leaks may be
required depending on European or local legislation.
Please contact your local dealer for more information.
• During the life-time of the system, inspection and tests
must be carried out in accordance with national
regulations.
VUGFB102
The information on operating inspections given in annex C
of standard EN278-2 can be used if no similar criteria exist
in the national regulations.
Safety device checks (annex C6 – EN378-2):
• The safety devices must be checked on site once a year
for safety devices (high-pressure switches), and every
five years for external overpressure devices (safety
globe valves).
• Check the "BW05 control" manual for a detailed
explanation of the high-pressure switch test method.
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. Each time repairs have been carried
out to the unit, the operation of the safety devices must be
re-checked.
If a leak occurs or if the refrigerant becomes polluted (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 R-407C charge, as indicated on the unit name plate. Do
not top up the refrigerant charge. Only charge liquid
refrigerant R-407C 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-407C) 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
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.
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 nitrogen.
Do not unweld or flamecut the refrigerant lines or any
refrigerant circuit component until all refrigerant (liquid
and vapour) has been removed from chiller. Traces of
vapour should be displaced with nitrogen. Refrigerant in
contact with an open flame produces toxic gases.
5