Basic Documentation

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Siemens Modular Heating Controller RMH760B CE1P3133en
Building Technologies 5 General functions, fundamentals 2017-09-29
Main menu > Settings > Boiler > Limitations
Operating line
Range
Factory setting
Frost prot boiler pump
Off / On
Off
The necessity for activating "Frost protection for the plant" is primarily dependent on the
type of hydraulic system and the location of the heating pipes in the building. If the
heating pipes are located such that they cannot be affected by frost, frost protection for
the plant will not be required.
The sequence of frost protection for the plant is as follows:
-2
OFF
0 1
2
3
4
-3
-4
-5
-6
-1
ON/OFF
ON
1 K
TO
TO
OFF
TO
ON
3131D09
TO
<–5 °C (TO
ON
)
-4…+2 °C
>2 °C (TO
OFF
)
Pump
Continuously on
On for 10 minutes every 6 hours
Continuously off
Status
ON
ON / OFF
OFF
Adjustable are the following temperatures:
• TO
ON
: Outside temperature at which "Frost protection for the plant" switches the
pump continuously on (frost protection for the plant continuously ON)
• TO
OFF
: Outside temperature at which "Frost protection for the plant" lets the pump
cycle (frost protection for the plant cycling ON)
In the event the outside sensor becomes faulty, frost protection for the plant will
continue to operate with a constant backup value of 0 °C outside temperature.
5.4 Pump overrun and mixing valve overrun
For all pumps (exception: circulating pump) and all mixing valves, overtemperature
protection can become active. Overtemperature protection always becomes active after
the burner has been shut down. To ensure that the heat consumers still draw heat for a
minimum period of time, an overrun time is enforced on the heat consumers that were
switched off within the last minute. During that overrun time, the pumps and mixing
valves continue to operate; the pumps continue to run and the mixing valves maintain
the "old" setpoint.
The duration of the overrun time is dependent on the type of heat source used and can
therefore be set on the boiler.
Main menu > Commissioning > Settings > … or
Main menu > Settings > Boiler > Limitations
Operating line
Range
Factory setting
Consumer overrun time
0…60 min
6 min
In order to also ensure overrun on plant with no system-internal heat exchanger,
overrun can also be set on the heat consumers.
Main menu > Settings > Protective functions
Operating line
Range
Factory setting
Consumer overrun time
0…60 min
6 min
Sequence of functions
Faulty outside sensor