Riello 20120391, Instructions For The Installer And For The Technical Support Service

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159
COMMISSIONING
INSTALLATION
Set the system's main switch to its "ON" position, and the de-
vice's main disconnecting switch to its "ON" position.
ON
OFF
ON
OFF
5.2 First commissioning
Before starting the unit always make sure you have read and
fully understood the operating instructions of the units and
make sure the following measures have been taken:
− check the heat transfer fluid circulation pumps, the air
treatment equipment and any other equipment con-
nected to the exchangers;
− make sure there are no refrigerant leaks;
− check the tightening of the retaining clips of all tubes;
− check the supply at the main connection point and
phase order;
− open the suction shut-off valves of each circuit for the
corresponding machines;
− check the operation of the compressor oil casing heating
elements 6 hours before starting the system;
− during start-up and testing, check that the system has
a thermal load and water flowing through the exchang-
ers;
− check that all setpoint adjustments and control tests are
carried out before starting the unit.
Now it is possible to proceed with the unit commissioning.
Check that all safety devices are in operation, in particular that
the high pressure switches are enabled and that any alarm is
removed.
9
For units without factory installed hydronic module, the
installer is responsible of the thermal protection and the
connections of the system pumps.
9
Commissioning and start-up must be supervised by a
qualified technician.
9
If the manufacturer's recommendations (system electri-
cal and hydraulic connections) are not complied with,
service calls under warranty will not be accepted.
5.3 Checks to be performed after the first
commissioning
After start-up:
− check that each compressor is rotating in the correct
direction, checking that the discharge temperature in-
creases rapidly, the HP increases and the LP decreases.
If it is rotating in the wrong direction, the power supply
is not wired correctly (inverted phases). To ensure the
correct rotation direction, invert the two power supply
phases.
− Check the compressor discharge temperature with a
contact sensor.
− Check the input current, that must be normal.
− Check all safety devices to make sure they work correctly.
− Check that the compressor's noise level is not abnormal
(knocking sound).
− Check that the device is operating under the recom-
mended operating conditions.
− When operating at maximum power (whether in cool-
ing or heating mode) the temperature difference of
approximately 5°C between delivery and return is re-
spected.
Upon commissioning the system overall pressure drop is un-
known. It will therefore be necessary to adjust the water flow
rate with the control valve until reaching the desired rated val-
ue.
By causing the reduction of the water pressure in the system,
the control valve aligns the pressure/flow curve of the system
with that of the pump, so that the rated flow rate correspond-
ing to the desired operating point is reached. The pressure
drop in the water exchanger (read through the pressure gauge
placed at exchanger inlet and outlet) is the reference to be
used to check and adjust the rated flow rate of the system.
To adjust the control valve:
− fully open the control valve
− leave the pump running for two hours to eliminate any
solid particles inside the circuit
− read the pressure drop in the water exchanger when the
pump is turned on and after two hours
− if the pressure drop is decreased, that means that the
shielding filter is clogged. It must be removed and
cleaned.
− Repeat the operation until the filter is completely clean.
− If the system pressure drops well below the available
static pressure provided by the pump, the water flow
rate will be low and the temperature difference between
exchanger inlet and outlet will be too high. For this rea-
son the pressure drops must be minimised. Check that
this difference falls within the curve values (refer to sec-
tion "System water content and flow rate").
9
Each unit is shipped with the exact refrigerant charge.
9
Should any of the above-listed controls have problems:
turn the device off and call the Technical Service imme-
diately.
9
If the unit is being controlled through the dry contacts, it is
recommended to shut off the unit when all the terminals
are shut off in order to avoid wasting energy unnecessarily.
0
It is forbidden to operate the device with a phase inverted.