Riello 20118250, Installation And Maintenance Manual

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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
3.2.7 Setting the domestic hot water parameters
The thermoregulation on the thermal unit allows having many
configurations for the management of the domestic hot water
production.
Domestic hot water request setting
When the temperature detected by the heater probe drops be-
low the DHW setpoint value (Par. 2047) minus the hysteresis val-
ue (Par. 2036) the regulator detects a domestic hot water request
and activates the circulator switching the 3-way diverting valve
on domestic circuit.
In this case, the circulator works with a setpoint (Par. 2049).
The burner turns on when the temperature detected by the de-
livery probe drops below the DHW setpoint value (Par. 2047) plus
the value defined in parameter 2038 minus 3°C (hysteresis), this
value corresponds by default to 69°C.
The request is met when the temperature detected by the heater
probe exceeds the DHW setpoint value (Par. 2047) plus the hys-
teresis value (Par. 2037).
The circulator carries on working for the post-circulation time
(Par. 2044).
The burner turns off when the temperature detected by the de-
livery probe exceeds the DHW setpoint value (Par. 2047) plus the
value defined in parameter 2038 plus 3°C (hysteresis), this value
corresponds by default to 75°C.