Hitecsa EQPL-B 4360 Manual Del Operador página 85

II.11.2 Special maintenance
These are all those repairs or replacements which allow the unit to keep on working in standard conditions. The spare parts must be identical to the
previous ones.
Control
Electrical system
Check the power consumption of the unit
Check electrical control board contactors
Fans
Electric motor of fans
Checking gas charge and humidity in circuit
(with unit running at full capacity)
Check that there are no gas leaks
Verify operation of maximum pressure
switches
Bleeding air from the chilled water system
Draining the water system
(if necessary)
II.11.2.1 Top-up / replacement of refrigerant charge
The units are factory-tested with the gas charge necessary for correct
operation. The amount of gas inside the circuit is shown directly on the
serial no. plate.
Should the R410A need to be topped-up, drain and evacuate the circuit,
eliminating traces of non-condensable gases with any humidity. After
maintenance operations on the cooling circuit and before restoring the
gas charge, wash the circuit thoroughly.
Then top-up the exact amount of new oil and refrigerant as shown on
the serial no. plate. The refrigerant must be drawn from the cylinder as
liquid so as to guarantee the correct mixture proportion (R32/R125).
Once the topping-up operation is complete, repeat the unit start-up
procedure and monitor its operating conditions for at least 24 hours.
If, for any particular reason, such as a refrigerant leak, you wish to
simply top-up the refrigerant, bear in mind that there may be a slight
drop in unit performance. In all cases the top-up must be carried out in
the low pressure section of the machine before the evaporator, using
the pressure sockets. Make sure that the refrigerant is introduced only
in the liquid phase.
II.11.2.2 Restoring compressor oil level
With the unit switched off, the oil level in the compressors must partially
cover the sight-glass on the level matching tube. The level is not always
constant as it depends on the ambient temperature and the percentage
of refrigerant in the oil.
With the unit on and in nominal conditions the oil level should be clearly
visible through the sight-glass and must be flat without any ripples.
An additional oil top-up can be carried out after evacuating the
compressors, using the pressure connection on the intake. For
information on the amount and type of oil, refer to the label on the
compressor or contact a HITECSA service centre.
Frequency
Besides checking the various electrical devices, the electrical
insulation of all the cables and their correct tightening on the terminal
Every 6 months
boards must be verified, paying special attention to the earth
connections.
Every 6 months
This operation must be carried out by skilled personnel of authorised
Every 6 months HITECSA workshops, qualified to operate on this type of products.
Make sure the motors and fan blades are clean and that there are no
Every 6 months
abnormal vibrations.
The motor must be kept clean with no traces of dust, filth, oil or other
impurities. These could cause it to overheat due to low heat
dissipation.
Every 6 months
The bearings are usually watertight with permanent lubrication and
sized in order to last approximately 20.000 hours in standard
operational and environmental conditions.
Every 6 months
Every 6 months
This operation must be carried out by skilled personnel of authorised
Every 6 months
HITECSA workshops, qualified to operate on this type of products.
Every 6 months
If the unit is idle during winter months, it must be emptied.
In alternative, a glycol mixture can be used according to the
information provided in this manual.
II.11.3

Always refer to the wiring diagrams enclosed with the appliance
when replacing electrically powered components. Always take care to
clearly label each wire before disconnecting, in order to avoid making
mistakes later when re-connecting.

When the machine is started up again, always go through the
recommended start-up procedure.

After maintenance has been performed on the unit, the liquid-
humidity indicator (LUE) must be under control. After at least 12 hours
of running, the refrigeration circuit of the unit must be perfectly "dry",
with the LUE green, Otherwise, the filter needs to be replaced.
II.11.3.1 Replacing the drier filter
To replace the drier filters, drain and eliminate humidity from the
refrigerant circuit by also draining the fluid dissolved in oil.
Once the filter has been replaced, evacuate the circuit again to
eliminate any trace of non-condensable gases, which could have
entered the system while replacing the filter. It is advisable to check that
there are no gas leaks before restarting the machine for normal working.
II.11.3.2 Instructions on how to drain the cooling
In order to drain the cooling circuit completely by means of type-
approved devices, drain the refrigerant from both the high and low-
pressure sides and in the liquid line. Use the load connections in every
section of the circuit. In order to drain the refrigerant fluid completely all
the circuit lines must be drained. The fluid must not be discharged into
the atmosphere as it causes pollution. It should be recovered in suitable
cylinders and delivered to a company authorised for the collection.
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SECTION II :: INSTALLATION AND MAINTENANCE
Notes
Repairing and replacing components
circuit