36
3.3.1 - HEATING MODE OPERATION
BY ROOM THERMOSTAT
By giving the 1
st
figure of the parameter
A the value 0 (e.g. A-0x) it means that
the request for more heat is driven by a
room thermostat.
A simple thermostat ON/OFF can be
used as room thermostat.
The setting of the flow (modulated) tem-
perature can be done by Parameter 3.
A communicating room thermostat can
also be used as remote control panel.
To this purpose Unical offers an inter-
face board, which will allow the boiler
and the room thermostat to communi-
cate.
The boiler will switch off, if the flow
3.3 - HEATING MODE
OPERATION
The boiler can fulfil different requests
for more heat by parameter A.
When leaving the workshop, the boiler
temperature exceeds by 5K the pre-
set flow temperature value (i.e. Pa-
rameter 3). The boiler will start again
as soon as the flow temperature has
gone under the pre-set value (Param-
eter 3) minus the heating system hys-
teresis (Parameter 8).
Heating Curve Parameters
The diagram beside is referring to the next
example:
Global flow temperature = 90°C
(param. 3)
Minimum global flow temperature = 15
°C (param 4)
Minimum outer temperature = -20°C
(param. 5)
Night shift = 10°C (param 7).
3.3.2 - HEATING MODE OPERATION
BY OUTDOOR SENSOR
By giving the 1
st
figure of the parameter
A the value 1 (e.g. A-1x) it means that
the request for more heat is driven by
an outer sensor. When the outer sen-
sor, which is normally supplied as stand-
ard, is installed, a heating curve is to be
determined.
The flow temperature will be calculated
in accordance with the detected outer
temperature.
The boiler will begin modulating accord-
ing to this flow temperature. When a
heating curve is set, the parameters on
the right are very important.
The boiler will switch off, if the flow
temperature exceeds by 5K the pre-
set flow temperature value (i.e. Pa-
rameter 3). The boiler will start again
as soon as the flow temperature has
gone under the pre-set value (Param-
eter 3) minus the heating system hys-
teresis (Parameter 8).
Parameter 3:
Maximum global flow temperature setting at the minimum
ou ter temperature
Parameter 4:
Minimum global flow temperature setting at the outdoor tempera
ture of 20°C
Parameter 5:
Minimum outdoor temperature
Parameter 6:
Temperature block upon request for heat. If, according to the
outdoor temperature, the flow temperature value is lower than the
parameter 6, there will be no heat request. This parameter can
be used in summer: when the outer temperature is high, a 25°C
regulation can be calculated whereas the parameter 6 can be
set to 30°C. In this case the request for heat will be stopped,
preventing the radiators from overheating.
Parameter 7:
The open contact of a room thermostat makes temperature de
crease during the night (night shift) - see note (*) on paragraph
3.2.8.2). The night temperature decrease can be set to 0 - 40K
by the parameter 7.
Parameter 8:
If it should be necessary to make a slight adjustment of the
measured outer temperature because, for instance, the outer
sensor NTC calibration tolerance is too high, it is possible to
make an adjustment of ± 5K on the measured value, by the
parameter 8.
Parameters to set by outdoor sensor.
has its parameter A set to 01 by default.
Its verification is however advisable at
boiler commissioning.
Fig. 19
100
90
80
70
60
50
40
30
20
10
0
-25
-20
-15
-10
-5
0
5
10
15
20
25
30
parameter 3
parameter 7
parameter 6
parameter 4
Global flow
temperature
°C
Outdoor temperature °C
Adjusting range of parameter 5
Ad
ju
s
ti
n
g
ra
n
g
e o
f
pa
ra
m
e
te
r 6
(1
5-3
0°
C
)
A
d
ju
st
in
g
r
a
ng
e
o
f
p
a
ra
m
e
te
r 3
(3
0
-9
0
°C
)
A
dj
u
s
tin
g r
ang
e
of
p
a
ra
m
ete
r 7
(0
-4
0
K
)
A
d
jus
ti
n
g r
a
ng
e
o
f
p
ar
am
et
er
4
(15-
60
°C
)