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11.3
Indirect hot water / calorifier
The following paragraphs
describe the different functions of the boiler and their related “controlling behaviour settings”
as a central heating boiler with an indirect hot water function.
11.3.1
PUMP AND
3-
WAY VALVE CONTROL
See chapter 19 for several installation examples of the boiler and the preferred functions. When the boiler is used as
an indirect boiler for both central heating and hot water function, this hot water function can be activated by using a
DHW pump or a 3-way valve.
P4 AB
DHW Pump Config 0=Pump 1=TWV (display B1)
With this parameter, it is programmed if the flow to the indirect water tank (calorifier) is controlled by a pump (0 =
Pump) or a 3-way valve (1 = TWV).
11.3.2
TANK THERMOSTAT
An external thermostat can be connected to the boiler. When there is a hot water demand and the tank thermostat
closes, the boiler will start for the hot water demand (connections 5-6). The calorifier/tank pump will be activated or
in case of a 3-way valve, this valve will turn to the position to supply heat to the tank coil(s). In case of a heat demand
and hot water demand, the (central) heating pump will switch off until the hot water demand ends.
P4 AB
DHW Pump Config 0=Pump 1=TWV (display B1)
With this parameter, it is programmed if the flow to the indirect water tank (calorifier) is controlled by a pump (0 =
pump) or a 3-way valve (1 = TWV).
11.3.3
TANK SENSOR
A tank sensor can be connected to the boiler. The tank (hot water) set point and related controlling parameters are
set in the boiler controller. A hot water demand is detected by the boiler, when the sensor (water) temperature drops
below the set point. The calorifier/tank pump will be activated or in case of a 3-way valve, this valve will turn to the
position to supply heat to the tank coil(s). In case of a heat and hot water demand at the same time, the heating pump
will switch off until the hot water demand is stopped (water temperature is reached).
P5 CA
Hysteresis DHW tank temperature (display BF)
The amount of degrees that the hot water temperature in the indirect water tank/calorifier needs to drop relative to
the hot water set point, before the heat demand is transported to the tank or is diverted to the tank coil(s).