Operating instructions

Heating mode
The control unit dete rmines a set boi l-
er water temperature subject t o the
outside tempera ture or room tempera-
ture (if a room temperature-dependent
remote control is connected) and the
slope/level of the heating curve. The
determined set boiler water t empera-
ture is transferred to th e burner con-
trol unit.
From the set and actual boiler water
temperatures , the burner contr ol unit
calculates the modulation level and
regulates the burner accordingly.
The boiler water te mperature will be
limited:
&
to 74 °C by the thermostat inside the
burner control unit.
&
to 82 °C by the electronic tempera-
ture limiter insi de the burner control
unit (during DHW heating to 87 °C).
&
to 100 °C by the temperature limiter
in the safety chain (interlocks t he
burner control unit).
Heating the DHW storage cylinder from cold
The heating circuit pump is switched
ON and the three- way diverter valv e
will be changed over, if the cylinder
primary temperature sensor captures
a temperature lower than the set tem-
perature.
&
At a boiler water temperature ≥ set
DHW temperature, the cylinder pri-
mary pump will be switched ON.
&
At a boiler water temperature ≤ set
DHW temperature, the burner will
be switched ON and, after the
required boiler water temperature
has been reached, the cylinder pri-
mary pump will be switched ON.
Thecylinderisthenheateduptothe
set DHW temperature. Heat ing stops
when the set temperat ure has been
reached at the cyl inder primary tem -
perature sensor and at the outlet tem-
perature sensor.
After heating, the cyl inder primary
pump and the three-way diverter
valve remain ON for a further 30 s.
Reheating when DHW is drawn off
When DHW is drawn off, cold water
enters at the bottom of the cylinder.
Weather–compensated control unit (cont.)
93
Function description
5692 619 GB