1 Setting point (parameter
)
2 Comfort base point (parameter
)
3 Gradient (parameter
)
F Heating curve
Outside temperature
Flow temperature
Frost protection combined with on/off thermostat
Tk On/off thermostat
Tv Frost thermostat
When an on/off thermostat is used, the pipes and radiators in a frost-sen
sitive room can be protected by a frost thermostat. The radiator valve in
the frost-sensitive room must be open.
1. Place a frost thermostat (Tv) in a frost-sensitive room (e.g. a ga
rage).
2. Connect the frost thermostat (Tv) parallel to the on/off thermostat
(Tk) on the On/Off OT terminals of the connector.
Important
When an OpenTherm thermostat is used, it is not possible to con
nect a frost thermostat parallel to the On/Off OT terminals. In that
case, implement frost protection of the central heating system in
combination with an outside sensor.
Frost protection combined with outside sensor
The central heating system can also be protected against frost in combina
tion with an outside sensor. The radiator valve in the frost-sensitive room
must be open.
1. Connect the outside sensor to the Tout terminals of the connector.
The frost protection works as follows with an outside sensor:
At outside temperatures below -10 °C: the circulation pump switches on.
At outside temperatures above -10 °C: the circulation pump continues to
run and then switches off.
Connecting the modulating regulator
OT OpenTherm regulator
The boiler is fitted with an OpenTherm connection as standard. As a re
sult, modulating OpenTherm thermostats (room-temperature, weather-
compensated and cascade thermostats) can be connected without further
modifications. The boiler is also suitable for OpenTherm Smart Power.
1. In the case of a room thermostat: install the thermostat in a refer
ence room.
2. Connect the two-wire cable to the On/Off OT terminals of the con
nector. It does not matter which wire is connected to which cable
clamp.
Fig.29
Internal heating curve
AD-0000871-02
20
10
0
-20
-10
15
30
45
60
75
90
0,5
1,0
1,5
2,0
2,5
F
3
2
1
Fig.30
Frost thermostat
AD-0000656-01
Pump
N L
+
0
+
0
0-10
PWM
Tout
OT
BL
RL
On/off
Tv
Tk
Fig.31
Outside sensor
AD-0000658-01
Pump
N L
+
0
+
0
0-10
PWM
Tout
OT
BL
RL
On/off
Fig.32
Modulating regulator
AD-0000653-01
Pump
N L
+
0
+
0
0-10
PWM
Tout
OT
OT
BL
RL
On/off
6 Installation
36
7625116 - v.04 - 17012017