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Siemens Building Technologies Basic Documentation RVL471 CE1P2524E
HVAC Products 25 Function block "Service functions and general settings" 23.10.2002
25.4.3 Manual overriding of operating mode (contact H1)
Using a simple remote operation facility, the operating mode of the heating circuit and
that of d.h.w. can be overridden. This is accomplished by bridging terminals H1−M.
It is possible to select the operating mode to be used when H1−M are bridged:
Setting Operating mode heating circuit Operating mode d.h.w.
0 Standby OFF
1 AUTO OFF
2 REDUCED OFF
3 NORMAL OFF
4 Standby ON
5 AUTO ON
6 REDUCED ON
7 NORMAL ON
8 AUTO ON (24 hours a day)
9 NORMAL ON (24 hours a day)
As long as this function is active, the LED of the respective operating mode button
flashes at a low frequency (approx. 0.5 Hz). The buttons themselves are however inop-
erable.
Once this function is deactivated, the RVL471 will resume the operating mode previ-
ously selected.
With plant types 4–x, 5–x, and 6–x, contact H1 only acts on the d.h.w. circuit.
25.4.4 Pump overrun
To prevent heat from building up, a common pump overrun time can be set for all
pumps associated with the controller (with the exception of the circulating pump) on
operating line 174. In that case, the pumps will overrun for the overrun time set, or the
diverting valve will maintain the charging position during that period of time.
D.h.w. discharging protection has priority over pump overrun.
In interconnected plants, the time set also affects the forced signals that a boiler can
deliver to ensure overtemperature protection.
For detailed information, refer to section “12.4.5 Protection against boiler overtem-
peratures”.
25.4.5 Pump kick
To prevent pump seizing during longer off periods (e.g. in the summer), it is possible to
activate periodic pump runs: The input is either “0” or “1”:
0 = no periodic pump kick
1 = periodic pump kick activated
If the pump kick is activated, all pumps run for 30 seconds, one after the other, every
Friday morning at 10:00, independent of all other functions and settings.
With plant types 2–1, 2–2, and 3–1, pump Q1 is kicked only when, at the same time,
charging pump Q3 does not operate.
25.4.6 Winter- / summertime changeover
The change from wintertime to summertime, and vice versa, is made automatically. If
international regulations change, the dates need to be re-entered. The entry to be
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