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Siemens Building Technologies
Basic Documentation RVL471
CE1P2524E
HVAC Products
16 Function block "Basic settings d.h.w."
23.10.2002
16 Function block "Basic settings d.h.w."
Function block "Basic settings d.h.w." is used to select the heating circuits for which the
d.h.w. is heated and according to which program the d.h.w. circulating pump shall op-
erate.
16.1 Operating lines
Line
Function, parameter
Unit
Factory
setting
Range
121
Assignment of d.h.w. heating
0
0...2
122
Program for the circulating pump
2
0...3
16.2 Assignment of d.h.w. heating
Operating line 121 is used to select for which heating circuits the d.h.w. is heated, that
is, which heating circuits draw their water from the same source.
Operating line 121 Explanation
0
D.h.w. heating is only provided for the heating circuit associated
with the own controller.
With plant types 4–x, 5–x, and 6–x, this setting makes no sense
since no own heating circuit exists (no d.h.w. in that case).
1
D.h.w. heating is only provided for the heating circuits of the con-
trollers with the same segment number that are connected to
the data bus (LPB).
2
D.h.w. heating is provided for all heating circuits of the controllers
connected to the data bus (LPB).
The setting is required in connection with operating lines 122 (circulating pump pro-
gram) and 123 (release of d.h.w. heating).
16.3 Program for the circulating pump
16.3.1
General mode of operation
On operating line 122, it is possible to enter according to which time program the d.h.w.
circulating program shall operate. The use of a circulating pump is optional with all
types of plant.
With d.h.w. plant type x–4 ”Instantaneous d.h.w. heating via heat exchanger”, it
is strongly recommended to use a circulating pump, the reason being better con-
trol performance.
That circulating pump runs only when d.h.w. heating is switched on (button is lit).
The circulating pump runs at the following times, depending on the setting made on
operating line 122:
Operating line 122 The circulating pump runs
0
Continuously (24 hours a day)
1
According to one or several heating programs
2
According to switching program 2 of own controller
3
According to switching program 3 of own controller