Siemens RVL471 - 23 Function Block Legionella Function; Operating Lines; Periodicity of Legionella Function; Time of Legionella Function

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Siemens Building Technologies Basic Documentation RVL471 CE1P2524E
HVAC Products 23 Function block "Legionella function" 23.10.2002
23 Function block "Legionella function"
In the case of d.h.w. heating systems with storage tanks, this function prevents the
formation of legionella viruses. This is accomplished by periodically heating the d.h.w.
to a certain temperature level.
23.1 Operating lines
Line Function, parameter Unit Factory
setting
Range
147 Periodicity of the legionella function 1 0...7
148 Time of legionella function hh:mm 05:00 00:00...24.00
149 Dwelling time at legionella setpoint min 30 0...360
150 Circulating pump operation during the legionella function 1 0 / 1
23.1.1 Periodicity of legionella function
The periodicity is displayed on operating line 147.
• Setting “0” ensures that d.h.w. heating to the legionella setpoint takes place once a day
• Settings “1” through “7” ensure that d.h.w. heating to the legionella setpoint takes place
once a week. Setting “1” means every week on Monday, setting “2” every week on
Tuesday, etc.
23.1.2 Time of legionella function
The time of day the legionella function shall be activated can be set on operating line
148.
23.1.3 Dwelling time at the legionella setpoint
Operating line 149 is used to determine for what period of time the actual d.h.w. tem-
perature must lie above the legionella setpoint (operating line 130) to satisfy the re-
quirement of this function.
23.1.4 Circulating pump operation during the legionella func-
tion
Operating line 150 can be used to select whether the legionella function shall act on the
d.h.w. circulating pump.
• When choosing “0”, the legionella function does not act on the d.h.w. circulating pump
• When choosing “1”, the legionella function acts on the d.h.w. circulating pump
23.2 Mode of operation
Preconditions for the legionella function:
• The d.h.w. storage tank temperature is acquired with one or 2 sensors (the legionella
function is not possible with thermostats)
• Charging takes place instantaneously with the heating water and not with the electric
immersion heater
• A legionella setpoint is adjusted
• D.h.w. heating is switched on (button
lit)
• The holiday function and operating mode changeover via contact H1 are not active