Gas Connection; Electrical Wiring; Filling The Heating System - Beretta MYNUTE GREEN 50 R.S.I. Manuel D'utilisation

3.6 Condensate collection
The system must be set up so as to avoid any freezing of the condensate
produced by the boiler (e.g. by insulating it). You are advised to install a
special drainage collection basin in polypropylene (widely available on
the market) on the lower part of the boiler (hole Ø 42), as shown in fig.18.
Position the flexible condensate drainage hose supplied with the boiler,
connecting it to the manifold (or another connection device which allows in-
spection) avoiding creating any bends where the condensate could collect
and possibly freeze. The manufacturer will not be liable for any damage
resulting from the failure to channel the condensate, or from its freezing.
The drainage connection line must be perfectly sealed, and well protected
from the risk of freezing. Before the initial start-up of the appliance, check
the condensate will be properly drained off.

3.7 Gas connection

The gas connection must be made respecting the installation regulations in
force, and sized to ensure the correct gas delivery to the burner.
Before making the connection, check that:
- the gas type is suitable for the appliance
- the piping is thoroughly clean
It is advisable to install a filter of suitable dimensions on the gas line if the
distribution network contains solid particles.
Once the appliance has been installed, check the connections are sealed
according to current installation regulations.

3.8 Electrical wiring

To access the electrical wiring, proceed as follows.
To access the terminal board:
- turn off the main switch on the system
- undo the fixing screws (D) on the housing (fig. 20)
- move the base of the housing forwards and then upwards to unhook it
from the chassis
- undo the fixing screws (E) from the instrument panel (fig. 20)
- lift then turn the instrument panel towards you
- loosen the screw that fixes the electric connections box, then remove the
box from its seat.
One side of the box contains the high voltage electric connections
(230V), while the other side contains the low voltage ones (fig. 23-24).
Refer to the wiring diagrams when making the connections. The connection
to the mains supply must be made via a separation device with an omnipolar
opening of at least 3.5mm (EN 60335-1, category III). The appliance operates
with an alternating current of 230 Volt/50 Hz and complies with the standard
EN 60335-1. It is obligatory to make the connection with a safe earthing, in
compliance with the current directives.
It is also advisable to respect the phase-neutral connection (L-N).
The earth wire must be a couple of cm longer than the others.
The boiler can operate with a phase-neutral or phase-phase supply. For
power supplies that are not earthed, it is necessary to use an isolating
transformer with earth-anchored secondary.
Do not use gas and/or water pipes to earth electrical
appliance.
Low voltage room thermostat input (24V DC).
The installer is responsible for ensuring the appliance is suitably
earthed; the manufacturer will not be liable for any damage resulting
from an incorrect or absent earth connection.
Use the power cable supplied to connect the boiler to the mains power
supply. If the power cable needs to be replaced, use a cable of the HAR
H05V2V2-F type, 3 x 0.75mm
7mm.
SAFETY
THERMOSTAT PRESSURE SWITCH
WARNINGS
- For the electrical wiring of the pressure switch and the I.S.P.E.S.L. safety
thermostat (if installed), refer to the enclosed diagram.
, with a maximum external diameter of
2
SAFETY
BOILER
3.9 Filling the heating system
Once the hydraulic connections have been carried out, fill the heating system.
This operation must be carried out with cold system following this instructions:
- open the plug of the boiler's automatic air vent (A) - fig. 31 by turning it
two or three times; to allow a continuous air discharge, leave the plug
open
- open the radiator drain valves
- turn on the filling tap (outside the boiler) and wait until the pressure indicated
on the hydrometer is between 1.5 bar and 2 bar. The filling procedure
must be carried out slowly, in order to free the air bubbles in the water
and allow them to be released via the boiler and heating system vents.
For the instructions on how to free the air bubbles, refer to the specific
paragraph
- close the filling tap
- close the radiator drain valves when only water begins to seep out of them.
WARNING: the boiler is not fitted with an expansion tank, so you must install
a closed tank on the system to ensure the appliance functions correctly.
The dimensions of the expansion tank must be suitable for the heating
system characteristics, and the tank capacity must meet the requisites of
the current regulations.
If the pressure value approaches 3.5 bar, there is the risk of the safety valve
being triggered. In this case, you should request the intervention of profes-
sionally qualified personnel.
Emptying the heating system
Before starting emptying, switch off the electricity supply by turning off the
main switch of the system.
- Turn off the heating system taps.
- Manually loosen the system drain valve (B) - fig. 32 - and connect the pipe
(supplied with the boiler) to it in order to drain the water into an external
container.
3.10 Bleeding the air from the heating circuit and boiler
During the initial installation phase, or in the event of extraordinary main-
tenance, you are advised to perform the following sequence of operations:
1. Use a CH11 spanner to open the manual air vent valve located above
the air distribution box (fig.15). Connect the tube (supplied with the boil-
er) to the valve, so the water can be drained into an external container.
2. Open the system filling tap located on the hydraulic unit and wait until
water begins to drain out of the valve.
3. Switch on the electricity supply to the boiler, leaving the gas tap turned
off.
4. Activate a heat request via the room thermostat or the remote control
panel, so that the 3-way valve goes into heating mode.
5. Activate a DHW request as follows:
heating-only boilers connected to an external storage tank: activate
the thermostat on the storage tank.
6. Carry on with the sequence until only water leaks out of the manual
air vent valve, and the air flow has stopped. Close the manual air vent
valve.
7. Check the system pressure level is correct (the ideal level is 1 bar).
8. Turn off the system filling tap.
9. Turn on the gas tap and ignite the boiler.
3.11 Circulator
Boilers are equipped with a circulator (already hydraulically and electrically
connected) whose effective performance levels are shown in the chart.
The boilers are equipped with an anti-blocking system which starts up
an operation cycle after every 24 hours of stop, with the mode selector
in any position.
The "anti-blocking" function is active only if the boilers are electrically
powered.
It is strictly forbidden to operate the circulator without water.
Maximum allowed water output <2200 l/h
A minimum output of 800 l/h must be guaranteed in the boiler, to
prevent the differential pressure switch being triggered.
To connect the system, we recommend the aid of a hydraulic separator
(supplied as an accessory), connected as shown in the diagrams
(fig. 8-9).
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