Maintenance - Mitsubishi Electric NX-W Installation And Operating Manual

UM_NX-W_00_05_19_ML
Check that the product and installation comply with the local regulations. In particular, make sure that the installation and commissioning certificates have been produced and
communicated.
The units must be started up by qualified personnel appointed by the manufacturer or his authorised representative (for contact details, refer to the information on the last page).
The authorised technical assistance centre will request the completion of the first start-up request form. The form must be returned to the authorised technical assistance centre
in order to plan the start-up of the unit.
Commissioning must be carried out by a Technician, in the presence of the Installer and an experienced Operator.
The Technician will test the equipment, carrying out checks, calibrations and commissioning according to the applicable procedures falling under his responsibility.
After the first few days of operation, the mesh filters of the hydraulic circuits must be checked and, if necessary, cleaned.
8.1 Adjusting the units
For adjustment and operation of the unit, refer to the user manual of the electronic controller.
9

MAINTENANCE

Maintenance operations are fundamental to keep the refrigeration system in perfect working order, not only for purely functional reasons but also for saving energy and ensuring
safety.
Each MEHITS Unit is supplied with a Machine Maintenance Logbook in which the user or person in charge of maintenance will log the operation of the MEHITS unit according to
the prescribed schedules. Lack of records in the logbook may be considered proof of improper maintenance.
When there are no relevant standards on the use of HFO refrigerants, the Manufacturer requires application and compliance with the provisions of:
- (EC) regulation no. 842/2006, Article 3 on "containment of leaks"
- (EC) regulation no. 1516/2007 on "standard leakage checking requirements"
and the relative domestic laws implementing the European regulations listed above.
9.1 Precautions that must be taken during maintenance
Maintenance must be carried out only by authorised technicians. Before any kind of maintenance is carried out the following measures must be observed:
•
the unit must be isolated from the electricity mains using the external main switch, suitable for the insertion of up to 3 padlocks, for locking in the "open" position;
•
hang a "Maintenance - do not switch on" sign on the main switch
•
use the appropriate personal protective equipment (hard hat, insulated gloves, protective glasses, safety footwear, etc.)
•
use tools that are in good condition and be sure to be familiar with the instructions before putting them into practice.
Whenever measurements must be taken or checks performed with the machine running, it is necessary to:
•
make sure that any remote control systems are disconnected; be aware that the PLC on the machine controls these and can enable and disable the components,
posing a degree of danger (for example, by powering and running the fans and their mechanical systems, which can drag);
•
work on the open switch board for as short a time as possible
•
close the switch board as soon as the single measurement or check has been performed
•
for external units, do not work on the machine in adverse weather conditions such as rain, snow, fog, etc.
Furthermore, the following precautions must always be taken:
•
the cooling circuit contains pressurised gas: all maintenance must be carried out by qualified personnel with the authorisation or certification required by the laws in
force
•
the fluids contained in the cooling circuit must be disposed of correctly
•
never keep the cooling circuit open, as the oil absorbs humidity and deteriorates
•
take measures to protect yourself from any leakage of fluids at dangerous temperatures during bleeding;
•
when replacing an EPROM or electronic cards, always use tools suitable for the task (extractors, anti-static bracelet, etc.)
•
if replacing a motor, compressor, evaporator, condensation batteries or any other heavy component, make sure that the lifting mechanism is suitable for the weight
to be lifted
•
Before generating a vacuum in the cooling circuit, make sure to disconnect from the power supply all the phases of the electric motor of the compressors by removing
or disconnecting the electrical protections (fuses and/or automatic switch) upstream of the cooling circuit; after performing the refrigerant charge, put the protections
back in place with the power turned off before start-up.
•
in the air units with a separate compressor compartment, do not enter the fan compartment without first having isolated the machine with the main switch on the
panel and hung out a "Maintenance - do not switch on" notice
•
contact MEHITS whenever modifications must be made to the cooling circuit, hydraulic or electrical diagram of the unit, or its control logic
•
contact MEHITS whenever particularly complicated disassembly or re-assembly operations need to be performed
•
only use original spare parts purchased directly from MEHITS or from official dealers
•
contact MEHITS if you wish to move the unit over a year from installation or when dismantling becomes necessary
•
make sure that all tools, electrical cables or loose objects have been removed and that the machine has been connected perfectly before closing and starting the
unit again
•
it is not permitted to walk on or place objects on the units. Any maintenance on the roof must be carried out using suitable equipment to guarantee safety, such as
bridging access platforms
•
some maintenance operations in the unit pose the risk of trapping: appropriate precautions must be taken.
MITSUBISHI ELECTRIC HYDRONICS & IT COOLING SYSTEM S.p.A. Translation of the original instructions
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EN