Stulz Cosmotec CVE Series, Use And Maintenance Manual

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CVE-CVO
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
Supervisors must be in constant contact with those in control
 Transit areas, stairs and doorways located near to the
equipment must not be obstructed.

Emergency exits must never be obstructed.

Slippery areas that constitute a potential risk to personnel must
be covered with a non-slip material.
 Specific tools and procedures must be adopted for each specific
activity.

Test equipment and tools must be maintained in good working
order.
 Personnel must have a detailed knowledge of the methods and
procedures adopted in the case of fire (place extinguishers within
easy reach)
11.2 HAZARDS DERIVING FROM CONTACT BETWEEN THE PRODUCT
AND PERSONS OR OBJECTS.

Hazard created by fan movement. The fan guard prevents the
passage of solid objects of dimensions exceeding 8mm

Danger due to possible accidental contact with the heat
exchanger whose aluminium fins may have sharp edges.

Do not pass any objects through the fan guard to check whether
the fan is operating
11.3 HAZARDS DERIVING FROM ELECTRICAL PROBLEMS
11.3.1 SAFETY STANDARDS FOR ELECTRICAL EQUIPMENT
Introduction
The causes of electrical hazards are well known, while their
prevention is not difficult providing constant attention is paid. In
order to reduce these hazards, personnel working with electricity
must be informed and instructed on the appropriate safety
procedures.
11.3.2 MANAGEMENT RESPONSIBILITIES
Managers must be informed of the potential hazards that exist in
the system and must supervise the personnel working on the
electrical equipment. This supervision activity consists of identifying
possible hazardous conditions and investigating the problems
encountered by personnel during maintenance operations. Each
defective component must be repaired or replaced immediately.
The manager must insist on the adoption of safety measures
without tolerating or accepting any deviations, otherwise damage
and or injury could result.
11.3.3 HIGH VOLTAGE
Contact with circuits through which high voltages pass can cause
burns, shock, unconsciousness and could even lead to death by
electrocution. This could be due to insufficient knowledge of the
dangers linked to electrical equipment. The damage caused to the
human body depends on the amount of current, its duration and
path taken by it through the human organism.
11.3.4 SAFETY STANDARDS TO RESPECT WHEN THE EQUIPMENT IS
SWITCHED OFF.

Disconnect the unit from the power supply before undertaking
any work
 However make sure that there is no voltage in the circuits.

Clean and dry the working area.
 Remove any pins, rings, straps or any other metal objects that
may interfere with the work or become potential conductors of
electricity.
 Make sure that the condensers connected to the deactivated
electrical circuit are discharged.

Remove the fuses only after the circuit has been deactivated.
11.3.5 SAFETY STANDARDS TO RESPECT WHEN CARRYING OUT
MAINTENANCE ON LIVE EQUIPMENT
In addition to that described in item 2.3.4, the following
requirements must also be complied with:
 Personnel must not work alone.

If possible, use one hand only to carry out the work.

Periodically check the instruments and the conductor wires.

Only follow authorised procedures when bypassing interlocks.

Make sure that the personnel assigned to do the work are
perfectly aware of the component parts of the equipment and the
maintenance procedures before starting any operations.

Wear a pair of insulated gloves.

Open all the contacts that feed power to the equipment before
measuring any resistance values.
 Make sure that there is no high voltage present in low voltage
circuits.

Do not use magnetic tools near to strong magnetic fields.
11.3.6 SAFETY STANDARDS TO RESPECT DURING MAINTENANCE
WORK
If continuous operation is not required, the system must always be
switched off.
Before carrying out any maintenance work:
 The maintenance technician must not be wearing any objects
that could act as conductors of electricity

The working area must be inspected and it must be ensured
that the floor is dry and clean

The working tools must be checked: in order to carry out the
work in safety, these must be suitable for the purpose and in good
condition
 Measuring instruments must be periodically calibrated

The working procedures must be checked prior to starting any
operations, referring to the wiring diagrams and taking note of how
the system is structured.
While performing electrical maintenance work:

The technician must be aware of circuits carrying high voltages

Resistance measurements must not be carried out on live
circuits
 Only one hand must be used for measuring live circuits

The instrument terminals must be grounded prior to measuring
live circuits
 The above suggestions must be followed carefully
Maintenance works are only deemed completed once all the
components have been reinstalled and the equipment is returned to
its normal condition.
11.4 FIRE HAZARDS
No direct danger of fire. Coolant gas in the presence of flame
develops toxic and corrosive substances. Refer to safety data sheet
of gas. Given the relatively low amount of gas contained in the air
conditioner, the risk prevention is to place the unit in sufficiently
ventilated rooms.
11.5 TOXIC SUBSTANCES
The gas in this unit is environmentally friendly and it is called R134a
(Tetrafluoroethane). It is of reduced amount and the circuit is
completely sealed. During the tests all leaks greater than 3 grams
per year are checked and removed. The coolant gas manufacturer
declares that gas concentrations less than 1/1000 are harmless. If