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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 chiller. Traces of
vapour should be displaced with dry air nitrogen. Refrige-
rant 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.
Avoid contact with liquid refrigerant on the skin or
splashing it into the eyes. Use safety goggles. 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.
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.
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
condi-tioning 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.
Any refrigerant transfer and recovery operations must be
carried out using a transfer unit. A 3/8” SAE connector on
the manual liquid line valve is supplied with all units for
connection to the transfer station. The units must never be
modified to add refrigerant and oil charging, removal and
purging devices. All these devices are provided with the
units. Please refer to the certified dimensional drawings for
the units.Do not re-use disposable (non-returnable)
cylinders or attempt to refill them. It is dangerous and
illegal. When cylinders are empty, evacuate the remaining
gas pressure, and move the cylinders to a place designated
for their recovery. Do not incinerate.
ATTENTION: Only use refrigerant R134a, in accordance
with 700 AHRI (Air conditioning, Heating and Refrige-
ration Institute). The use of any other refrigerant may
expose users and operators to unexpected risks.
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.
1.4 - Repair safety considerations
It is compulsory to wear personal protection equipment.
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 R-134a charge, as indicated on the unit name plate.
Certain parts of the circuit can be isolated. Only charge
liquid refrigerant R-134a 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-134a) 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.
RISK OF EXPLOSION:
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