Beretta Mynute Boiler Green 25 B.S.I. E Manuel D'installation Et D'utilisation page 11

If the calculation produces an intermediate value between two
curves, you are advised to choose the compensation curve nearest
the value obtained.
Example: if the value obtained from the calculation is 1,3 this is
between curve 1 and curve 1,5. Choose the nearest curve, i.e. 1,5.
Select the KT using trimmer P3 on the board (see multiwire wiring
diagram).
To access P3:
- switch off the power supply
- remove the shell
- turning the instrument panel towards you
- unscrew the two screws of the small cover on the electronic
board to have access to the terminals
Live electrical parts.
The KT values which can be set are as follows:
standard installation: 1,0-1,5-2,0-2,5-3,0
floor installation 0,2-0,4-0,6-0,8
and these are displayed for approximately 3 seconds after rotation
of the trimmer P3.
TYPE OF HEAT REQUEST
Boiler connected to room thermostat (JUMPER JP6 not
inserted)
The heat request is made by the closure of the room thermostat
contact, while the opening of the contact produces a switch-off.
The delivery temperature is automatically calculated by the boiler,
although the user may modify the boiler settings. Using the interface
to modify the HEATING, you will not have the HEATING SET-
POINT value available, but a value that you can set as preferred
between 15 and 25°C. The modification of this value will not directly
modify the delivery temperature, but will automatically affect the
calculation that determines the value of that temperature, altering
the reference temperature in the system (0 = 20 °C).
Boiler connected to a programmable timer (JUMPER JP6
inserted)
With the contact closed, the heat request is made by the delivery
sensor, on the basis of the external temperature, to obtain a nominal
indoor temperature on DAY level (20°C). With the contact open, the
boiler is not switched off, but the weather curve is reduced (parallel
shift) to NIGHT level (16°C).
This activates the night-time function.
The delivery temperature is automatically calculated by the boiler,
although the user may modify the boiler settings.
Using the interface to modify the HEATING, you will not have the
HEATING SET-POINT value available, but a value that you can set
as preferred between 25 and 15°C.
The modification of this value will not directly modify the delivery
temperature, but will automatically affect the calculation that
determines the value of that temperature, altering the reference
temperature in the system (0 = 20°C for DAY level, and 16°C for
NIGHT level).
4.7 Adjustments
The boiler has already been adjusted by the manufacturer during
production. If the adjustments need to be made again, for example
after extraordinary maintenance, replacement of the gas valve,
or conversion from methane gas to LPG, observe the following
procedures.
The adjustment of the maximum and minimum output, and of
the maximum and minimum heating and of slow switch-on, must
be made strictly in the sequence indicated, and only by qualified
personnel only:
- disconnect the boiler from the power supply
- remove the shell
- turning the instrument panel towards you (fig. 7)
- unscrew the two screws of the small cover on the electronic
board to have access to the terminals
- insert the jumpers JP1 and JP3
- power up the boiler.
The display shows "ADJ" for approximately 4 seconds.
Next change the following parameters:
1 - Domestic hot water/absolute maximum
2 - Minimum
3 - Heating maximum
4 - Slow switch-on
as follows:
- turn the heating water temperature selector to set the required
value
- press the CO button (fig. 9) and then skip to the calibration of the
next parameter.
Live electrical parts.
The following icons light up on the monitor:
1. during domestic hot water/absolute maximum calibration
2. during minimum calibration
3. during heating maximum calibration
4. during slow switch-on calibration
End the procedure by removing jumpers JP1 and JP3 to store
these set values in the memory.
The function can be ended at any time without storing the set
values in the memory and retaining the original values as follows:
- remove jumpers JP1 and JP3 before all 4 parameters have been set
- set the function selector to
- cut the power supply 15 minutes after it is connected.
Calibration can be carried out without powering up the boiler.
By turning the heating selection knob, the monitor
automatically shows the number of rotations, expressed in
hundreds (e.g. 25 = 2,500 rpm).
The function for visualizing the setting parameters is activated by
the function selector in summer and in winter, by pressing the CO
button on the circuit board, either with or without request for heat.
This function cannot be activated when connected to a remote
control.
Upon activating the function the setting parameters are visualized
in the order given below, each for 2 seconds. Each parameter is
displayed together with its corresponding icon and fan rotation
speed measured in hundreds
1. Maximum
2. Minimum
3. Max. heating
P
4. Slow ignition
5. Max. preset heating
GAS VALVE CALIBRATION
- Connect the boiler to the power supply
- Open the gas tap
- Set the function selector to
- Loosen the screws (A), remove the housing, then lower the
instrument panel towards you (fig. 6-7)
- Unscrew the two screws of the small cover on the electronic
board to have access to the terminals
- While the boiler is powered up, using a small screwdriver
included, press the CO button (fig. 9).
Live electrical parts.
- Wait for burner ignition.
The boiler operates at maximum heat output.
The "combustion analysis" function remains active for a limited time
(15 min); if a delivery temperature of 90°C is reached, the burner
is switched off. It will be switched back on when this temperature
drops below 78°C.
- Insert the analyser probe in the ports provided in the air
distribution box, after removing the screws from the cover (fig.
19)
- Press the "combustion analysis" button a second time to reach
the number of rotations corresponding to the maximum domestic
hot water output (table 1)
- Check the CO value: (table 3) if the value does not match the
2
value given in the table, use the gas valve maximum adjustment
screw
- Press the "combustion analysis" button a third time to reach the
number of rotations corresponding to the minimum output (table 2)
- Check the CO value: (table 4) if the value does not match the
2
value given in the table, use the gas valve minimum adjustment
screw
Mynute Boiler Green B.S.I. E
(OFF/RESET)
(OFF/RESET) (monitor off)
11