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Building Technologies
Modular Heating Controller RMH760B
CE1P3133en
HVAC Products
10 DHW heating
05.02.2007
Main menu > Commissioning > Settings > …
or
Main menu > Settings > DHW > Controller primary circuit
Operating line
Range
Factory setting
[Tn] return temp limitation max
0…60 min
30 min
The return temperature sensor must be assigned a terminal via “Extra configuration”:
Main menu > Commissioning > Extra configuration > DHW > Inputs > Return sensor
Assign
terminal
The function is to be activated via “Settings“:
Main menu > Commissioning > Settings > …
or
Main menu > Settings > DHW > Limitations
Operating line
Range
Factory setting
DHW return temp max
---- / 0…140 °C
---- °C
Legionella return temp max
----/ 0…140 °C
---- °C
This limitation is active provided a valid value has been set and the legionella function
is active. The limitation can be overridden by return temperature limitation in connection
with the legionella function.
Maximum limitation with DHW heating is constant, that is, independent of the outside
temperature.
Maximum limitation of the return temperature during DHW heating will be deactivated.
Maximum limitation of the return temperature is constant during the time the legionella
function is active, that is, independent of the outside temperature. This limitation too will
be activated only when a valid value has been set. If the value is invalid (“---“), there
will be
no
limitation during the time the legionella function is active.
10.8.3 Frost protection functions
Frost protection for the DHW storage tank is ensured in all operating modes and is
activated as soon as one of the 2 storage tank sensors acquires a temperature below
5 °C.
A temperature request will then be sent to the heat source, and the storage tank heated
up until both storage tank temperatures have reached 5 °C (plus the adjusted switching
differential) thereby exceeding 6 °C, independent of the operating mode.
Frost protection for the storage tank is started when the plant operation selector is set
to “Off“ and / or in summer operation the storage tank is charged via the electric immer-
sion heater.
With plant types DHW 2 through DHW 5, the flow temperature is monitored also.
If it falls below 5 °C, the primary pump will be activated with plant type DHW 2, and the
secondary pump with all the other plant types. When the temperature exceeds 6 °C, the
pump will be switched off again.
During the time frost protection for the flow is active, no heat request is sent to the heat
source.
10.8.4 Pulse limitation
DHW heating can handle pulses for limiting the output or the volumetric flow. Prerequi-
site for pulse limitation is a DHW plant type with mixing valve, that is, DHW 2, DHW 3,
DHW 4, or DHW 6.
Extra configuration
Settings
Return temperature
limitation during DHW
heating
Return temperature
limitation during the
time the legionella
function is active
Frost protection for
the storage tank
⇒
Frost protection for
the flow