Beretta CIAO AT 29 C.S.I. Installer And User Manual page 8

ENGLISH
4.5 Setting the thermoregulation
The thermoregulation only operates with the external sensor connected;
once installed, connect the external sensor (accessory available on
request) to the special terminals provided on the boiler terminal board
(fig. 6).
This enables the THERMOREGULATION function.
Selecting the compensation curve
The compensation curve for heating maintains a theoretical temperature
of 20°C indoors, when the external temperature is between +20°C
and -20°C. The choice of the curve depends on the minimum external
temperature envisaged (and therefore on the geographical location),
and on the delivery temperature envisaged. It is carefully calculated by
the installer on the basis of the following formula:
envisaged delivery T. - Tshift
KT=
20- min. envisaged external T.
Tshift = 30°C standard installations
If the calculation produces an intermediate value between two curves,
you are advised to choose the compensation curve nearest the value
obtained.
Select the KT using trimmer P3 on the board (see multiwire wiring
diagram). To access P3:
- loosen the screws (A) that hold the housing in place (fig. 14)
- unscrew the screw (B) that secures the control panel (fig. 15)
- rotate the control panel towards you
- remove the terminal board cover (fig. 15).
Live electrical parts (230 V AC).
The KT values which can be set are as follows:
standard installation: 2,0-2,5-3,0
and these are displayed for approximately 3 seconds after rotation of
the trimmer P3.
The value of the thermoregulation curve is by default 2.0. Is
not recommended to fall below this value.
TYPE OF HEAT REQUEST
Boiler connected to room thermostat (JUMPER 6 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).
4.6 Adjustments
The boiler is factory-set by the manufacturer.
If it is necessary to adjust it again, for example after extraordinary
maintenance, after replacement of gas valve or after gas conversion,
carry out the following procedure.
The maximum output adjustment must be carried out in the
sequence indicated exclusively by qualified personnel.
- remove the housing by loosening the fixing screws A (fig. 36)
- loosen the screw of the pressure test point downstream from the gas
valve by roughly two turns, then connect the pressure gauge
- disconnect the compensation inlet from the air distribution box
4.6.1 Maximum power and minimum domestic hot water
adjustment
- Turn on a hot water tap to its maximum output on the control panel:
- set the function selector to
- turn the domestic hot water temperature selector to its maximum
(fig. 37b)
8
(graphs 1-2-3, page 65)
(summer) (fig. 37a)
- power the boiler electrically by setting the main system switch to
"ON"
- check the pressure on the pressure gauge is stable, or use a
milliammeter connected to the modulator to make sure the latter is
receiving the maximum available current (120 mA for G20 and 165
mA for LPG)
- use a screwdriver to carefully prise the protection cap out of the
adjustment screws
- using a fork spanner CH10 on the maximum output adjustment nut
to obtain the value indicated in the data table
- disconnect a modulator faston
- wait until the pressure shown on the pressure gauge is stable at
minimum value
- use an Allen spanner to set the red adjustment screw of the DHW
minimum, calibrating it until the pressure gauge shows the value
indicated in the data table
- reconnect the modulator faston
- turn off the domestic hot water tap
- carefully refit the protection cap of the adjustment screws.
4.6.2 Minimum and maximum heating electric adjustment
The "electric adjustment" function is activated and deactivated
exclusively by the jumper (JP1) (fig. 39).
ADJ appears on the display, indicating that the calibration procedure
is in progress.
The function can be enabled in the following ways:
- by powering the card with jumper JP1 inserted and the function
selector in the winter position, regardless of the possible presence of
other operation requests.
- by inserting jumper JP1, with the function selector in the winter
position, without any heat request in progress.
By activating the function the burner is ignited through simulation
of heat request in heating.
To perform calibration operations, proceed as follow:
- switch off the boiler
- remove the housing and the terminal board cover, loosening the
screw B (fig. 39) to access the card
- insert jumper JP1 (fig. 39) to enable the minimum/maximum heating
adjustment functions of the knobs on the control panel.
- make sure the function selector is in the winter position (see
paragraph 4.2).
- power the boiler
Electric card live (230 Volt)
- turn the heating water temperature adjustment knob B (fig. 40) until
it reaches the minimum heating value as indicated in the multigas
table
- insert jumper JP2 (fig. 39)
- turn the DHW temperature adjustment knob C (fig. 40) until it reaches
the maximum heating value as indicated in the multigas table
- remove jumper JP2 to store the maximum heating value
- remove jumper JP1 to store the minimum heating value and to
quit the calibration procedure
- reconnect the compensation inlet to the air distribution box.
Disconnect the pressure gauge and re-tighten the pressure test point
screw.
To finish the calibration function without storing the set values, proceed
as follows:
a) set the function selector to
b) remove power supply voltage
c) remove JP1/JP2
The calibration function is automatically finished, without storing
minimum and maximum values, after 15 minutes of its activation.
The function is automatically finished also in case of definitive
stop or lockout. Also in this case, function conclusion DOES NOT
provide values storing.
Note
To calibrate maximum heating only, you can remove jumper JP2 (to
store the maximum) and then quit the function without storing the
minimum, bringing the function selector to
the power supply to the boiler.
After each intervention on the adjustment element of the gas
valve, seal it with sealing varnish.
When adjustment is complete:
- bring the temperature set via the ambient thermostat back to the
required value
OFF
(OFF) or disconnecting