Siemens RVL471 - Operation of Circulating Pump During the Holiday Period

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Siemens Building Technologies Basic Documentation RVL471 CE1P2524E
HVAC Products 16 Function block "Basic settings d.h.w." 23.10.2002
With setting 1, operation of the circulating pump depends on the setting made on oper-
ating line 121. In an interconnected plant with several controllers, that is, with several
heating programs, the circulating pump runs when at least one of the controllers pro-
vides heating to the NORMAL temperature according to its heating program (independ-
ent of the operating mode) and is not in holiday mode.
The circulating pump runs with a forward shift against the times of the heating program;
this means it is affected by optimum start control.
With plant types 4–x, 5–x, and 6–x and the setting of “0” (own controller) on operating
line 121, the circulating pump never runs since these plant types have no own heating
program.
2 examples are given below to show the behavior of the circulating pump when con-
trollers A, B, C and D are interconnected via data bus:
Operating
line 121
Operating
line 122
Con-
trollers
Operating
mode
Heating program,
holidays
A
06:00...18:00
1B
07:00...23:00
C
07:00...22:00
2
D
03:00...22:00,
HOLIDAYS
The circulating
pump runs from
06:00:00 to
23:00
Operating
line 121
Operating
line 122
Con-
trollers
Operating
mode
Heating program,
holidays
A
06:00:00..0.18:00,
optimum start con-
trol shifts forward
by 2 hours
B
08:00...23:00
C
07:00...22:00
21
D
05:00...21:00
The circulating
pump runs from
04:00:00 to
23:00
16.3.2 Operation of circulating pump during the holiday
period
During the holiday period, the circulating pump runs according to the setting made, as
shown in the following table:
Operating
line 121
Operating
line 122
Operation of circulating pump
0 0, 1, 2, or 3 Circulating pump OFF, if own controller in holiday mode
1 0, 1, 2, or 3 Circulating pump OFF, if all controllers having the same
segment number are in holiday mode
2 0, 1, 2, or 3 Circulating pump OFF, if all controllers in the intercon-
nected system are in holiday mode
Example 1
Example 2