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Start-up
5 START-UP
The unit must be started for the first time by
personnel suitably trained by one of
A
uthorised Service Centre. Fail
ure
to meet this requirement will immediately
void the warranty.
The operations carried out by
authorised
personnel are limited to the start-up of
the unit, and do not include any other ope-
ration on the plant, such as, for example,
electrical and hydraulic connections etc. All
the other operations before start-up, inclu-
ding oil pre-heating for at least 12 hours,
must be performed by the Installer.
5.1 Preliminary check
The checks listed below shall be performed before
starting the unit and before the arrival of the person-
nel authorised.
Q
Check the section of power supply and grounding
cables; make sure that terminals are tightened and
check the correct operation of contactors, with the
master switch open.
Q
Check that any voltage and phase variation in the
power supply does not exceed the prefixed thre-
sholds.
Q
Connect the contacts of the flow switch and the
thermal relay of the pump and of the other devices
(if any), to terminals 1-2 and 3-4, respectively.
Q
Check that the components of the external water
circuit (pump, user equipment, filters, power sup-
ply tank and reservoir, if any) have been installed
properly, and according to the manufacturer’s
instructions.
Q
Check the filling of the hydraulic circuits, and
make sure that the fluid circulation is correct,
without any trace of leaks and air bubbles. If you
use ethylene glycol as antifreeze, check that its
percentage is correct.
Q
Check that the direction of rotation of the pumps
is correct, and that fluids have been circulating for
at least 12 hours for both pumps. Then, clean the
filters on the suction side of the pumps.
Q
Adjust the liquid distribution network in such a
way that the flow rate is within the specified ran-
ge.
Q
Check that the water quality is up to the specifica-
tions.
Q
Check that oil heaters, if any, have been turned on
at least 12 hours before.
5.2 Start-up
Start-up sequence:
Q
Turn on the master switch (at least 12 hours befo-
re).
Q
Check that the oil in the compressor has reached
the requested temperature (the minimum tempera-
ture outside the pan must be approx. 40°C) and
that the auxiliary control circuit is energised.
Q
Check the operation of all the external equipment,
and make sure that the control devices of the plant
are properly calibrated.
Q
Start the pump and check that the water flow is
correct.
Q
Set the desired fluid temperature on the control bo-
ard.
Q
Start the appliance (see Chapter 6).
Q
Check the correct direction of rotation of compres-
sors. Scroll compressors cannot compress the refri-
gerant when they rotate in the opposite direction.
To make sure that they are rotating in the correct
direction, simply check that, just after the start-up
of the compressor, the pressure drops on the LP
side and rises on the HP side. Furthermore, if a
scroll compressor rotate in the opposite direction,
there is a considerable rise in the sound level of
the unit, as well as in a dramatic reduction of cur-
rent absorption compared to normal values. In
case of wrong rotation, the scroll compressor can
be definitely damaged.
Q
After about 15 minutes of operation check that the-
re are no bubbles, through the sight glass on the
liquid line.
The presence of bubbles may indicate that
a part of the refrigerant charge has been re-
leased in one or more points. It is important
to remove these leaks before proceeding.
Q
Repeat the start-up procedure after removing the
leaks.
Q
Check the oil level in the compressor’s sight glass.
WARNING
WARNING
NOTE
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