S T A R T I N G U P - Hitecsa CED 11.1 Instrucciones De Instalación, Funcionamiento Y Mantenimiento

S T A R T I N G U P

START-UP PROCEDURE AND CHECKLIST
The refrigerant load in air-cooled and split systems is a particularly important aspect in the correct operation of the entire
installation; it is therefore necessary this process be done by an expert Refrigeration Contractor following the indications
given in the previous pages. The system is to be loaded only with the refrigerant gas indicated on the unit identification label.
START-UP OF FAN SECTION
Check that the power, as prescribed by the system design, reaches terminals R-S-T, that the neutral is wired to terminal N
and that the circuit is adequately earthed.
If, temporarily, there is no requirement to operate the other parts of the air-conditioning system (which, depending on the
ambient conditions, could start-up automatically) disconnect the relevant interruptor switches.
Push the ON button if the unit is equipped with the microprocessor controller, and, if not, activate via the switch on the front
of the indoor unit, and in this way the fans will start.
N.B. On the CED units the fan motors are almost always single phase and therefore the direction of rotation is factory set.
On other special units or CEM units the fan motors are three phase and therefore one has to check the correct direction of
rotation. To see if a motor is single or three phase it is sufficient to check the electrical diagrams supplied with the unit.
When belt drive fans are used, always check the tension of the belts and the alignment of the pulleys, even if these are
always checked during factory tests (see the MAINTENANCE section).
THE FANS MUST NOT BE ALLOWED TO RUN WITH THE PANEL OPEN FOR MORE THAN 20 SECONDS.
Verify the input power of the electric fan motors, which must be contained within the values indicated on the identification
plate of the motors.
If the engaged power / current is higher because the external pressure drops have been overestimated, then it is necessary
to block part of the supply or return airflow, or even to block part of the air passage on the fan mouth, in order to return within
the limits indicated on the identification label. Then, if a single phase fan-motor is fitted (CED), it is possible to adjust the
airflow by acting on a speed regulator (if fitted).
START-UP OF COMPRESSOR SECTION
Close the interruptor switches opened during start-up of the fan section and check that all wiring is tightly screwed into its
terminal.
Set all the adjustments on the microprocessor control or, if not fitted, on the thermostats in order to provoke the start-up of
the compressor.
The compressors will only operate if ambient conditions exceed the limits set on the temperature control of the indoor unit.
Check that the relay switches, that control the delay/time interval of the starts of the compressors, have been set for at least
3 minutes between starts in order to avoid that a compressor starts too frequently.
It is also a good idea that the different relay switches, in units with more than one compressor, be set with different time
intervals in order to avoid compressors staring together. For those air-conditioners that are equipped with the microprocessor
controller, the delay/time-interval has been already set in the control itself and the time delays are indicated in the specific
manual for the microprocessor control.
The start of the compressors will provoke the start of the condenser fan(s) once consent has been given by the High
Pressure switch or the Modulating Control of the condenser.
The settings on the pressure regulators are normally factory set. To change or readjust these, the following procedure
applies:
•
ON-OFF control of condensing pressure: reselect the setting on the pressure switch
•
electronic MODULATING control of condensing pressure: act on the transducer in a clockwise direction to increase
the condensing pressure and
indications as to the various types of condensing pressure regulators that are normally used.
Check that the input power of the compressors is lower than that indicated on the identification plate, and check also that the
refrigerant gas load is complete.
05.08 Ref.200989 Rev.100
anti-clockwise to reduce the condensing pressure. See Fig.10/11 for
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