42
COMMISSIONING AND MAINTENANCE
Mode 3
: continuous operation with fixed setpoint and night re-
duction with ambient thermostat (AT)
In this mode:
− External probe is not required.
− The OpenTherm (OT) communication is not enabled and
any OT thermostat connected is supplied but signals a
“communication error”.
− Input 0-10V is not used.
− The Modbus communication is not enabled.
The fixed setpoint adjustment procedure is the same of mode 0.
The only difference is that the request is always active and the
setpoint is decreased (night reduction) by the value defined by
the parameter 2133 upon the opening of the ambient thermo-
stat/heat request contact.
Par. No. Description
2103
Main Zone/Zone 1 setpoint in heating mode Par.
2001= 0 and 3.
The thermal unit adjustment determines the boiler
setpoint in heating mode, using the highest value
among the requests of all the active zones (Par. 1101,
1201, 1301).If Zone 1 is set as mixed, the value set in
parameter 1112 will be used as setpoint.
2023
Minimum heating setpoint.
2024
Maximum heating setpoint.
2133
Main Zone/Zone 1 setpoint night reduction in heat-
ing mode Par. 2001=2 or 3.
It defines by how many degrees the heating set-
point will be reduced at the opening of the ambi-
ent thermostat (AT) contact.
The reduction of the delivery temperature affects all
the active heating zones and it can be used when
the AT terminal of every zone regulator is jumpered.
T delivery
(°C)
T outside (°C)
Tset min (°C)
Tset max (°C)
Setpoint @TA=ON
Par. 2024
Par. 2023
Par. 2133
Par. 2103
Setpoint @TA=OFF
Mode 4
: operation with variable setpoint according to the value
of the input signal 0-10V
In this mode:
− External probe is not required.
− The OpenTherm (OT) communication is not enabled and
any OT thermostat connected is supplied but signals a
“communication error”.
− The Modbus communication is not enabled. If a device
is connected to the Modbus, the values on the remote
device are not updated.
The parameters regulating such temperature are:
Par.
No.
Description
2023
It limits the minimum value that can be assigned to
the setpoint in heating mode.
2024
It limits the maximum value that can be assigned to
the setpoint in heating mode.
2025
It defines the delivery temperature minimum value
in heating mode (Par. 2001 = 4).
2026
It defines the delivery temperature maximum value
in heating mode (Par. 2001 = 4).
The operation set-point is adjusted on the basis of the following
curve:
T delivery
(°C)
Voltage (V)
Par. 2024
Par. 2025
Par. 2026
Par. 2023
3.2.6
Setting the domestic hot water parameters
The check of the temperature on the plate exchanger for the do-
mestic hot water production is carried out through the reading
of the temperature probes at exchanger inlet (DCW) and outlet
(DHW).
The check of the domestic water temperature is controlled
through the circulator modulation.
The exchanger, as factory setting, is kept at a minimum temper-
ature of 60°C (Par. 2056).
The activation of the domestic circuit request is carried out if
the temperature detected by the probe at exchanger inlet (DCW)
decreases rapidly or drops below 25°C (Par. 2052), in this case the
burner turns on (if off), the 3-way diverting valve switches on
domestic circuit and the circulator will activate.
The request is met when the temperature detected by the probe
at exchanger inlet (DCW) exceeds the 28°C (Par. 2053 + 3°C), in
this case the circulator turns off but the 3-way diverting valve
stays in domestic water position until the next request.
