Auxiliary Functions; Frost Protection For The Plant; Pump Overrun - Siemens RVP360 Basic Documentation

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17.4 Auxiliary functions

17.4.1 Frost protection for the plant

The plant can be protected against frost. Precondition is that controller and heat
source are ready to operate (mains voltage present!).
The following settings are required:
Outside temperature at which frost protection shall respond
Minimum flow temperature to be maintained by the frost protection function
0,5 °C 0,5 °C
ON
OFF
BZ 167
If the current outside temperature falls below the limit value (setting on operating
line 167 minus 0.5 °C), the controller switches heating circuit pumps M2/M6 on and
maintains the flow temperature at the setpoint selected for frost protection (operat-
ing line 168).
An appropriate heat request is sent to the heat source.
The control is switched off when the outside temperature exceeds the limit value
by 0.5 °C.
Frost protection for the plant can be deactivated (setting --.- on operating line 167).

17.4.2 Pump overrun

To prevent heat from building up, a common pump overrun time can be set on
operating line 174 for all pumps associated with the controller (with the exception
of the circulating pump). So, upon deactivation, the pumps continue to run for the
set overrun time.
D.h.w. discharging protection has priority over the pump overrun function.
In interconnected plants, the set time also affects the forced signals that a boiler
can deliver to ensure overtemperature protection.
For more detailed information, refer to chapter 12.4.5 "Protection against boiler
overtemperatures".
Basic Documentation RVP360
17 Function block: Service functions and general settings
BZ167
T
A
OFF
ON
T
A
Operating line 167
Outside temperature
Frost protection OFF
Frost protection ON
CE1P2546en
2017-07-24