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7
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 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. 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.
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
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.
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 Refrigeration
Institute). The use of any other refrigerant may expose users
and operators to unexpected risks.
Do not attempt to remove refrigerant circuit components or
fittings, while the machine is under pressure or while it is
running. Be sure pressure is at 0 kPa before removing components
or opening a circuit.
Do not attempt to repair or recondition any safety devices when
corrosion or build-up of foreign material (rust, dirt, scale, etc.)
is found within the valve body or mechanism. If necessary,
replace the device. Do not install relief valves in series or
backwards.
Summary of Contents for 30HXC Series
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