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Building Technologies
Modular Heating Controller RMH760B
CE1P3133en
HVAC Products
10 DHW heating
05.02.2007
This defines the time of day the legionella function shall be started.
It is defined here for what period of time the DHW temperature shall be maintained at
the legionella protection setpoint.
Using setting “On“ on operating line
Circulating pump operation legio
, the circulating pump
will be activated according to the following rule, independent of the pump’s time pro-
gram:
In the case of DHW plant types with storage tanks, the circulating pump starts to run as
soon as the storage tank temperature has reached the level of “Legionella protection
setpoint minus switching differential”. With direct DHW heating, the circulating pump
always runs when the legionella function is active.
If the circulating pump operates due to its time program, this setting will have no im-
pact. This means that the setting will activate a stopped pump, but will not deactivate a
running pump.
10.6.3 Legionella function relay
The state of the legionella function can be delivered via a configurable output for further
handling.
The output changes to “On“ as soon as the legionella function is started and remains
on until the function is ended.
The output is to be activated via “Extra configuration”:
Main menu > Commissioning > Extra configuration > DHW > Outputs > Legionella function
relay
Assign terminal
There are no settings required.
10.7 Primary
control
With plant types DHW 1 and DHW 5, the charging temperature is not controlled. But it
can be indirectly influenced by appropriate selection of DHW priority or by the tempera-
ture request.
Charging is effected through control of the secondary pump or primary pump based on
the storage tank temperature.
The other plant types are also controlled via the storage tank temperature but, in addi-
tion, the secondary temperature or the primary flow temperature will be controlled.
With plant type DHW 6, primary control is always enabled while the secondary flow
temperature is controlled.
With plant types DHW 2 and DHW 4, control is accomplished via a mixing valve, with
plant types DHW 3 and DHW 6 via a 2-port valve.
The setpoint for primary control is dependent on the operating mode and, according to
plant type, on the respective setpoint increase.
Control can be effected with a 3-position or DC 0…10 V actuator. The type of actuator
is to be selected via “Extra configuration”.
The following settings apply to both the 3-position and the DC 0…10 V actuator.
Legionella protection time
Legionella protection
period
Legionella protection and
circulating pump
Extra configuration
Settings
Plant types
DHW 1 and DHW 5
DHW 2, DHW 3 and
DHW 4
DHW 6
Primary control
Setpoint
3-position or
DC 0…10 V actuator