Important; Anti-Freeze System; Gas Connection; Electric Connection - Beretta Mynute Boiler Green 25 B.S.I. Manual De Instalador Y Usuario

ENGLISH
For correct appliance positioning:
- do not place it on a cooker or other cooking device
- do not leave inflammable products in the room where the boiler
is installed
- heat sensitive walls (for example, wooden walls) must be
protected with proper insulation.

IMPORTANT

Before installation, wash every system piping carefully in order to
remove any residues that may impair the operation of the appliance.
Under the safety valve, install a water collecting funnel with
the corresponding discharge in the event of leaks due to the
overpressure of the heating system. The domestic hot water circuit
does not need a safety valve, but make sure that the pressure
of waterworks does not exceed 6 bar. In case of doubts, install a
pressure reducer.
Prior to ignition, make sure that the boiler is designed to operate
with the gas available; this can be checked by the message on the
packaging and the adhesive label indicating the gas type.
It is very important to highlight that in some cases the smoke pipes
are under pressure and therefore, the connections of several
elements must be airtight.

ANTI-FREEZE SYSTEM

The boiler is fitted as standard with an automatic anti-freeze system
that activates when the temperature of the water in the primary
circuit falls below 5°C. This system is always active, guaranteeing
boiler protection to an outdoor temperature level of 0°C. To take
advantage of this protection (based on burner operation), the boiler
must be able to switch itself on; any lockout condition (e.g. lack
of gas/electricity supply, or safety device intervention) therefore
deactivates the protection. The anti-freeze protection is also active
when the boiler is on standby. In normal operation conditions,
the boiler can protect itself against freezing. If the machine is left
unpowered for long periods in areas where temperatures may fall
below 0 °C, and you do not want to drain the heating system, you
are advised to add a specific, good quality anti-freeze liquid to the
primary circuit. Carefully follow the manufacturer's instructions with
regards not only the percentage of anti-freeze liquid to be used for
the minimum temperature at which you want to keep the machine
circuit, but also the duration and disposal of the liquid itself.
For the domestic hot water part, we recommend you drain the
circuit. The boiler component materials are resistant to ethylene
glycol based anti-freeze liquids.
3.2 Cleaning the system and characteristics of the
heating circuit water
In the case of a new installation or replacement of the boiler, it is
necessary to clean the heating system.
To ensure the device works well, top up the additives and/or
chemical treatments (e.g. antifreeze liquids, filming agents, etc.)
and check the parameters in the table are within the values
indicated.
Unit of
Parameters
measurement
pH value -
Hardness °F
Appearance -
Fe mg/kg
Cu mg/kg
3.3 Securing the boiler to the wall and hydraulic
connections
To fasten the boiler to the wall, use the crossbar (fig. 1) in the
packaging. The position and size of the hydraulic connections are
indicated below:
A CH return 3/4"
B CH delivery 3/4"
C

gas connection

3/4"
D DHW output 1/2"
E
DHW input 1/2"
If water hardness exceeds 28°Fr, it is recommended to use
water softeners, to prevent any limestone deposit in boiler due to
excessively hard water.
3.4 Installation of the external sensor (fig. 3)
The correct operation of the external sensor is fundamental for the
good operation of the climate control.
6
Hot water
Filling water
circuit
7-8 -
- <15
- clear
0,5 -
0,1 -
INSTALLING AND CONNECTING THE EXTERNAL SENSOR
The sensor must be installed on an external wall of the building to
be heated, observing the following indications:
it must be mounted on the side of the building most often exposed
to winds (the NORTH or NORTHWEST facing wall), avoiding direct
sunlight; it must be mounted about two thirds of the way up the wall;
it must not be mounted near doors, windows or air outlet points,
and must be kept away from smoke pipes or other heat sources.
The electrical wiring to the external sensor is made with a bipolar
cable with a section from 0.5 to 1 mm
maximum length of 30 metres. It is not necessary to respect the
polarity of the cable when connecting it to the external sensor.
Avoid making any joints on this cable however; if joints are
absolutely necessary, they must be watertight and well protected.
Any ducting of the connection cable must be separated from live
cables (230Vac).
FIXING THE EXTERNAL SENSOR TO THE WALL
The sensor must be fixed on a smooth part of the wall; in the case
of exposed brickwork or an uneven wall, look for the smoothest
possible area. Loosen the plastic upper protective cover by turning
it anticlockwise.
After deciding on the best fixing area of the wall, drill the holes for
the 5x25 wall plug. Insert the plug in the hole. Remove the board
from its seat.
Fix the box to the wall, using the screw supplied. Attach the bracket,
then tighten the screw. Loosen the nut of the cable grommet, then
insert the sensor connection cable and connect it to the electric
clamp.
To make the electrical connection between the external sensor and
the boiler, refer to the "Electrical wiring" chapter.
Remember to close the cable grommet properly, to prevent
any humidity in the air getting in through the opening.
Put the board back in its seat.
Close the plastic upper protective cover by turning it clockwise.
Tighten the cable grommet securely.
3.5 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. 5. Position the flexible
condensate drainage hose supplied with the boiler, connecting it to
the manifold (or another connection device which allows inspection)
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.
3.6 Gas connection
Before connecting the appliance to the gas supply, check that:
- national and local installation regulations are complied with
- the gas type is the one suitable for the appliance
- the piping is clean.
The gas pipe must be installed outdoors. If the pipe goes through
the wall, it must go through the central opening, in the lower part
of the template.
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.

3.7 Electric connection

To access the electrical wiring, proceed as follows:
- turn off the main switch on the system
- loosen the fixing screws (A - fig. 6) and remove the shell
- release the panel and turn it forwards
- unscrew the two screws of the small cover on the electronic
board to have access to the terminals
Connect the appliance to the mains power supply with a switch
featuring a distance of at least 3,5 mm (EN 60335-1, category III)
between each wire.
(not supplied), with a
2