26
COMMISSIONING - WARNINGS
COMMISSIONING - WARNINGS
Please note that, on request by the Aermec customer or the legitimate
owner of the machine, the units in this series can be started up by the
AERMEC After-Sales Service in your area (valid only on ITALIAN territory).
The start of operation must be scheduled in advance based on the time
frame for the completion of works for the system. Prior to the intervention,
all other works (electrical and hydraulic hook-ups, priming and bleeding of
air from the system) must have been completed.
START-UP
OPERATIONS TO BE PERFORMED WITH NO VOLTAGE PRESENT
ATTENTION
the unit is not working:
Check:
- All safety conditions have been respected
- The unit is correctly fixed to the support surface
- The minimum technical spaces have been respected
- That the main power supply cables have appropriate cross-section,
which can support the total consumption of the unit. (see electric data
sections) and that the unit has been duly connected to the ground.
- That all the electrical connections have been made correctly and all
the terminals adequately tightened.
OPERATIONS TO BE PERFORMED WITH THE UNIT LIVE
ATTENTION
the unit is still not working:
- Supply power to the unit by turning the main switch to the ON
position.
- Use a tester to check that the value of the supply voltage to the
U.V.W. phases lies within the tolerance range, and also check that the
unbalance between the phases does not exceed 3%.
- Check that the connections made by the installer are in compliance
with the documentation.
- Verify that the resistor of the compressor sump is working by
measuring the increase in temperature of the oil pan. The resistance/s
must function for at least 12 hours before start-up of the compressor
and in any event, the temperature of the oil pan must be 10-15°C
higher than room temperature.
HYDRAULIC CIRCUIT CONTROLS
- Check that all hydraulic connections have been made correctly, that
the information on the plates has been observed and that there is a
filter upstream of the entire WWM line.
(Mandatory component for
warranty to be valid).
- Make sure that the circulation pump/s is operating and that the water
flow rate is sufficient to close the contact of the flow switch, if installed.
- Check the water flow rate, measuring the pressure difference between
inlet and outlet of the evaporator and calculate the flow rate using the
evaporator pressure drop tables present in this manual.
- Check the correct functioning of the flow meters if installed. Closing
the cut-off valve at the output of the heat exchanger; the unit control
panel must show the block. Finally re-open the valve and rearm the
block
COMMISSIONING
- Once all the aforementioned checks have been carried out, the unit
can be commissioned
- Close the door of the electrical panel.
- Set the unit main switch to ON, the unit will start after a few minutes
OPERATIONS TO BE PERFORMED WITH MACHINE ON
ATTENTION
the unit is working:
Check:
- That the compressor input current is lower than the maximum
indicated in the electrical data table.
- Before starting the unit, check that the compressor rotates in the
correct direction through a three-phase protection. The spiral
compressors compress in one direction of rotation only. Therefore, it
is essential for the phase of the three-phase spiral compressors to be
correctly connected (the correct direction of rotation can be controlled
when the pressure on the intake side decreases and that on the flow
side increases with the compressor in operation). If the connection is
incorrect, the direction of rotation is reversed: this causes a loud noise
and the reduction of current consumption. In this case, the protection
system inside the compressor activated turning off the unit. To solve
the problem, disconnect and swap the wires between two of the
phases, then connect the three-phases again.
- That the voltage value lies within the pre-fixed limits and that
unbalance between the three phases (three-phase power supply) is
not above 3%.
- If having to take measurements and perform checks that require the
machine to run, you must:
- make sure that any remote control systems are disconnected; however,
keep in mind that the PLC on the machine controls its functions and
can enable and disable the components creating hazardous situations
(e.g. power and rotate the fans and their mechanical drive systems).
- Operate with the electrical board open the shortest time possible
- Close the electrical board as soon as the single measurement or
control is performed
ATTENTION
The anti-freeze set temperature can only be varied by an authorised
after-sales centre and only after having checked that there is a suitable
% of anti-freeze solution in the water circuit.
Whenever this alarm intervenes, call the nearest authorised after-sales
service immediately
- Control of the water flow rate alarm, the unit provides for the
management of a flow rate alarm controlled by a differential pressure
switch or flow switch if provided. This type of safety device intervenes
after the first 30 seconds of pump functioning, if the water flow rate is
not sufficient. The intervention stops the compressor and the pump
itself.
