23
ADJUSTING THE FUNCTIONAL PARAMETERS
2 DHW_Type
Boiler type (parameter 6)
0 = No DHW service
1 = Quick exchanger with sensor
2 = Boiler with sensor
6 = Boiler with thermostat
In the case of a boiler with a thermostat, if the input is a closed
contact, the DHW demand is activated, if it is an open contact
the demand stops.
Preset to 0.
3 DHW_Priority
DHW priority (parameter 9)
0 = Shifting priority A
The purpose of shifting priority function A is that the system can
also serve heating if the heating demand is low.
The system responds to the heating demand if:
(Setpoint_Ch - 50°C) < Temp_collettore < (Setpo 1°C)
Setpoint_Ch = Setpoint of the high or low temperature circuit
depending on demand.
1 = Shifting priority B
The purpose of shifting priority function B is that the system
never stops the heating service for too much time.
The system responds to the heating demand if:
(SetpoT_Tank_extra) - 50°C < Temp_collettore < (Set-
poi T_tank_extra) + 1°C
T_tank_extra = Par. 10 = preset to 30°C.
2 = Absolute priority (only DHW service)
Preset to 0.
9.3
Heat control setting
1 Attenuation_High
HIGH TEMPERATURE circuit attenuation function (parameter
21)
There are 2 cases:
− Fixed point operation Par. 14=0
− Operation with climatic control Par. 14=1.
FIXED POINT OPERATION, PAR. 14=0
With the high temperature circuit attenuation disabled, Par21=0
when the high temperature circuit thermostat is closed, the
heating demand is activated. When opened, the system turns
off.
The Master control unit activates the high temperature circuit
pump PZ1 and the system pump PZ2 (if parameter P34=0).
On the Master control unit it is possible to set the high tem-
perature circuit setpoint, Setpoint_T_CH_High = Par. 1, preset to
70°C and settable from 10°C to T_CH_high_limit=Par 17, which is
in turn preset to 80°C. The setpoint used will be the one set with
parameter 1.
The burner is on when:
Manifold temperature <=Setpoint – ignition hysteresis.
Ignition hysteresis can be set, CH_High_hyst_on = Par. 19, preset
to 7°C, can be set between 0 and 20°C.
The Master control unit converts the heat demand into power
demand for each slave control unit.
The burners are off when:
Manifold temperature >=Se shut-off hysteresis .
Shut-off hysteresis can be set (CH_High_Hyst_off=Par. 20, preset
to 3, can be set between 0 and 20°C).
With the high temperature circuit attenuation parameter, Par.
21
≠
0, the high temperature thermostat contact is ignored and a
heat demand is present for the high temperature circuit when:
Manifold temperature <=Setpoint – ignition hysteresis
The heat demand stops when:
Manifold temperature >=Se shut-off hysteresis .
The setpoint in this case coincides with the value set for param-
eter 1 (Setpoint_t_ch_high) if the high temperature thermostat
contact is closed, whereas it is calculated as the value set for
parameter 1 less the attenuation (Setpoint_t_ch_high-Attenua-
tion_high) if the contact is open.
OPERATION WITH CLIMATIC CONTROL, PAR. 14=1
If the high temperature circuit attenuation is equal to 0 , Atten-
uation_high=Par. 21=0, its behaviour is the same as the previous
paragraph, with the exception that the setpoint is calculated
based on the outdoor temperature.
If the outdoor temperature = Tout_min=Par. 37, preset to 0°C,
then setpoint =setpoint_T_Ch_high.
If the outdoor temperature = Tout_max=Par. 38, preset to 18°C,
then setpoint T_ch_high_ foot=Par. 18, preset to 50°C.
The setpoint is calculated linearly between the 2 outdoor tem-
perature values.
Preset to 0.
2 Attenuation_Low
LOW TEMPERATURE circuit attenuation function (parameter
25)
This paragraph is similar to the previous paragraph for the low
temperature circuit.
There are 2 cases:
− Fixed point operation Par. 22=0
− Operation with climatic control Par. 22=1.
FIXED POINT OPERATION, PAR. 22=0
With low temperature circuit attenuation disabled, Par. 25=0 at
the closure of the low temperature circuit thermostat, heating
demand is activated. When opened, the system turns off.
The Master control unit activates the low temperature circuit
pump if the parameter for the third pump is set to 1 (P34=1).
On the Master control unit, it is possible to set the low temper-
ature circuit setpoint, Setpoint_T_CH_Low = Par. 3, preset to 40°C
and can be set between 10°C and T_CH_low_limit=Par. 23, which
in turn is preset to 50°C. The setpoint used will be the one set
with parameter 3.
The burner is on when:
Manifold temperature <=Setpoint – ignition hysteresis.
Ignition hysteresis can be set, CH_Low_hyst_on = Par. 26, preset
to 5°C, can be set between 0 and 20°C.
The Master control unit converts the heat demand into power
demand for each slave control unit.
The burners are off when:
Manifold temperature >=Se shut-off hysteresis .
Shut-off hysteresis can be set (CH_Low_Hyst_off=Par. 27, preset
to 3, can be set between 0 and 20°C).
With the low temperature circuit attenuation parameter, Par.
25
≠
0, the low temperature thermostat contact is ignored and a
heat demand is present for the low temperature circuit when:
Manifold temperature <=Setpoint – ignition hysteresis
The heat demand stops when:
Manifold temperature >=Se shut-off hysteresis .
The setpoint in this case coincides with the value set for param-
eter 3 (Setpoint_t_ch_low) if the low temperature thermostat
contact is closed, whereas it is calculated as the value set for
parameter 3 less the attenuation (Setpoint_t_ch_low-Attenua-
