
Expert area
Part 2: Overview of display values and settings
28
Hot-Water
Designation Value
range
Standard
IV
DHW Relief
Off/On
On
Parallel DHW
Partial DHW,
On, Off,
Parallel all
Partial
DHW
T-HS DHW
00K – 50K
20K
Hysteresis DHW
5K – 30K
5K
DHW Followup
00min – 30min 00min
Therm Input
Off/On
Off
Wall Hung
Off/On
Off
Load Through
Off/On
Off
Use the F button [End] to exit the level
DHW Relief
(DHW Relief)
The charging pump is not switched until the boiler
temperature exceeds the storage tank temperature by
5K. It is switched off when the boiler temperature drops
below the storage tank temperature. This prevents the
storage tank from being cooled by the boiler when hot
water preparation starts.
Parallel DHW
(Pump parallel running)
Partial DHW => Partial priority HW: The heating circuits
are blocked during hot water preparation. The mixers
close and the heating circuit pumps switch off. The mixer
circuits are enabled again when the boiler has reached
the temperature of hot water temperature s boiler
superheating [T-DHW + T-HS DHW]. If the boiler
temperature drops below the enable temperature by the
switching hysteresis [Hysteresis DHW] again, the mixer
circuits are blocked again.
On => Pump parallel running: Only the direct heating
circuits are blocked during hot water preparation. The
mixer circuits continue to be heated. The hot water
preparation is extended by this function.
Off => Warm water priority operation: The heating circuits
are blocked during hot water preparation. The mixers
close and the heating circuit pumps switch off.
Parallel all => Pump parallel running also for the direct
heating circuit: During hot water preparation all heater
circuits continue to be heated. The hot water preparation
is extended by this function. When the boiler temperature
exceeds the maximum flow temperature of the direct
heating circuit by 8K, the heating circuit pump for this
circuit is switched off (overheating protection). The
heating circuit pump is switched on again when the boiler
temperature drops below the temperature [maximum flow
tempe 5K].
T-HS DHW
(increase during HW operation)
Heat generator setting with hot water preparation = hot
water temperature s T-HS DHW
!
The boiler must be run at a higher temperature
during hot water preparation so that the hot water
temperature in the storage tank can be reached via
the heat exchanger.
Hysteresis DHW
(hot water hysteresis)
Hot water preparation is started when the temperature of
the hot water storage tank drops below the temperature
setting by the hysteresis [Hysteresis DHW]. The hot water
preparation stops when the storage tank reaches the
temperature setting (the temperature setting is set to
65°C during hot water short time heating operation).
DHW Followup
(pump run-down time)
00min => Standard function: The charging pump
continues to run for 5 minutes after the burner has
switched off.
If heat is requested by a heating circuit the run-down is
cancelled.
The charge pump blocking kicks in and can also cause
the run-down function to be cancelled.
greater than 00min => The charge pump runs down by
the set time when storage tank charging is complete. The
after-run can only be cancelled by the activated charge
pump blocking.
Therm Input
(storage tank with thermostat)
00 => Hot water preparation via storage tank sensor
01 => Hot water preparation via thermostat:
The hot water preparation is started by a short circuit at
the storage tank sensor connecting terminals. It stops
when the short circuit is removed.
Wall Hung
(for modulating HS)
Boiler temperature setting with hot water preparation =
hot water actual tempe T-HS DHW
With this function the exhaust gas losses occurring during
hot water preparation can be reduced with modulating
heat generator using the adapted boiler temperature
setting.
Load Through
(only with F12 = T-DHW B)
The charge through function can be activated by
connecting a hot water storage tank bottom sensor.
T-DHW = Temperature of hot water tank in removal area
Storage tank charging:
ON: T-DHW < T-DHW Rated - Hysteresis DHW
OFF: T-DHW B > T-DHW Rated
The charging process of the storage tank only terminates
when the lower storage tank set temperature has been
reached.