Instructions For Startup; Configuration; Starting The Unit; Prolonged Shutdown - Hitecsa EWNLM 115 Manuel D'utilisation

II.7

INSTRUCTIONS FOR STARTUP

IMPORTANT!
Machine commissioning or the first start up (where
provided for) must be carried out by skilled
personnel from workshops authorised by HITECSA
qualified to work on this type of product.
IMPORTANT!
The use and maintenance manual regarding the
pumps and safety valves (where present is attached
to this manual and must be read thoroughly.
IMPORTANT!
Several hours before start-up (at least 12) apply
voltage to the machine in order to power the
electrical resistances for heating the compressor
guard. These resistances disconnect automatically
at every machine start-up.
DANGER!
Before starting up, make sure that the installation
and electrical connections conform with the
instructions in the wiring diagram. Also make sure
that there are no unauthorised persons in the
vicinity of the machine during the above operations.
DANGER!
The 122÷240 units are equipped with safety valves
positioned inside the technical compartment; their
intervention causes a noise and violent sprays of
refrigerant and oil. It is prohibited to approach the
safety valves intervention pressure value. The
safety valves are conveyable according to that
prescribed by the manufacturer f the valves
themselves.
II.7.1

CONFIGURATION

Safety component calibration settings
Interventio
Pressure switch
high pressure
low pressure
water differential
safety valve
on the high pressure
DANGER! (122÷240)
The safety valve on the high pressure side is
calibrated at 41.7 bar. This could intervene if the
calibration value is reached during the loading
operations of the refrigerant, inducing a leak that
could cause burns (as the other valves in the
circuit).
Configuration parameters
Summer working temperature set-point
Winter working temperature set-point (EWNHM)
45°C Working temperature differential
2°C Antifreeze temperature set-point
2.5°C Antifreeze temperature differential
2°C Water differential pressure switch time upon start-up
120" Water differential pressure switch exclusion time upon start-up
15" Circulation pump switch off time delay
15" Minimum time between two consecutive compressor start-ups
360"
The units are tested in the factory, where they are also calibrated and
the default parameter settings are put in. These guarantee that the
appliances run correctly in rated working conditions. Machine
configuration is carried out in the factory and should never be altered.
Reset
n
40.2 bar 28 bar - Automatic
2 bar 3.3 bar - Automatic
80 mbar 105 mbar - Automatic
41.7 bar -
Standard setting
DANGER!
Always use the master switch to isolate the unit
from the mains before carrying out any
maintenance work on the unit, even if it is for
inspection purposes only. Make sure that no one
accidentally supplies power to the machine – lock
the master switch in the zero position.
IMPORTANT!
If a unit is used for the production of chilled water,
check the adjustment of the thermostatic valve.
II.7.2

STARTING THE UNIT

Before starting the unit, perform the following checks:
○ The electricity power supply must comply with the specifications on
the data plate and/or the wiring diagram and it must fall within the
following limits:
Variation of the power supply frequency: ±2 Hz;
variation of the power supply voltage: ±10% of the nominal voltage;
imbalance between the supply phases: <2%.
○ the electrical power supply system must be able to supply adequate
current and be suitably sized to handle the load;
○ open the electric panel and make sure the terminals of the power
supply and of the contactors are tight (they may have come loose
during transport, which could lead to malfunctions);
○ check that the water system inlet and outlet pipes are connected in
accordance with the arrows next to the machine water inlet/outlet;
Electrical connections must be made in compliance with the local
installation standards in force in the place where the unit is installed,
and with the instructions in the wiring diagram provided with the unit.
For the sizing of the supply cables, refer to what is set out in the wiring
diagram.
IMPORTANT!
On three-phase models, before connecting the main
power supply cables L1-L2-L3+N to the terminals of
the general isolator, make sure that they are in the
right order.
The machine can be started by pressing the ON/OFF key on the
keyboard built into the machine. Using the MODE key, select an
operating mode (chiller or heat-pump). Any problems the system
encounters will be immediately shown on the display on the control
keyboard. At start-up, the first device to start in the system is the pump,
which has priority over the rest of the system. During this phase, the
minimum water flow differential pressure switch and the low pressure
switch are ignored for a preset time, in order to avoid variations caused
by air bubbles or turbulence in the water circuit or by pressure
fluctuations in the cooling circuit. Once these time-delays are over, final
enabling is given to the machine, followed after another safety time-lag
by the compressor.
II.7.3

PROLONGED SHUTDOWN

7°C
IMPORTANT!
If the unit is not used during the winter period, the
water contained in the system may freeze.
When the machine is out of use for long periods of time, it is necessary
to disconnect it from the mains by opening the master switch.
All the water contained in the circuit must be drained in good time.
During installation, consider mixing the water in the circuit with the
correct proportion of ethylene glycol to guarantee protection against
freezing.
II.7.4

STARTUP AFTER PROLONGED SHUTDOWN

Before starting up again, make sure that:
there is no air in the water system (bleed it if necessary);
water in the heat exchanger is circulating in the required amount.
37
SECTION II: INSTALLATION AND MAINTENANCE