AQUA
4
–AGU-1405-E
- 48 -
-
Drain the expansion vessel until the pressure reaches 0.5 bar
-
Fill the system and pressurise it to approxi 1 bar in pump suction (pump stopped)
-
Bleed the system
-
Check the pump suction pressure (approximately 1 bar) and start up the system
-
Stop the pump after 15-30 minutes. Repeat the procedure from step 3 until no more air system noise can be heard.
12.4 Electrical connections
Check that the mains electricity supply is compatible with the specifications (voltage, number of phases, frequency) shown on the unit
rating plate.
The supply voltage must not fluctuate more than ±5% and the imbalance between phases must always be below 2%.
Cary out the electrical connections following the wiring diagram provided with the unit, as well as current regulations.
An earth connection is
mandatory
: The installer must connect the earth wire to the earth terminal on the electrical panel (yellow and
green wire).
The power supply to the control circuit is shunted from the power line through an electric panel transformer.
The control circuit is protected by fuses or automatic switches, depending on the size of the unit.
12.5 Electric connections of the circulation pump
All the units of the LER series are provided with a voltage-free contact on the electrical panel that powers the pump start consent.
Remote Controls
To remotely switch on and switch off the unit, remove the jumper between the contacts and connect the remote control to the terminals
(see attached wiring diagram). Enable the “REMOTE” function with the electric panel switch.
Remote Summer-Winter switching (AQUA
4
M Versions )
To remotely switch the unit from the summer to the winter modes, remove the jumper between the contacts and connect the remote
control to the terminals (see attached wiring diagram). Enable the “REMOTE” function with the electric panel switch.
The diagrams were plotted with a temperature differential at the plate exchangers (water circuit) of 5°C
12.6 Use of glycol solutions
Water can be produced at temperatures below 5°C (up to -10°C) using glycol solutions. This lowers the freezing point as shown in the
following table:
Minimum temperature of
produced water
5 °C
2°C
-1 °C
-5°C
-10 °C
Percentage in weight of
ethylene glycol
0 %
10 %
15%
25 %
30 %
Freezing temperature of
mixture
0 °C
-4 °C
- 8 °C
-14 °C
-18 °C
For solution concentrations up to 30% in volume of glycol, the drop in thermodynamic circuit performance is minor.
The AQUA
4
units are not guaranteed for applications in circuits with propylene glycol mixtures.
12.7 Operating and storage limits
-
Heat transfer fluid: water or mixtures of water and ethylene glycol (max. 30% in volume)
The pump, when an integral part of the supply, must be started before the cooler starts and stopped after it
stops (minimum recommended start delay: 60 seconds). If it is connected to the electric panel terminal, this
function is already performed by the onboard microprocessor
The machine must operate within the above values, or the warranty will be invalidated.
The size of the cable and line protections must conform to the specifications provided in the wiring diagram.
Before carrying out any operation on electrical parts, make sure that the power supply is disconnected.
