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Building Technologies
Boiler sequence controller RMK770
CE1P3132en
HVAC Products
7 Boiler control
23.04.2009
Using this setting, the boiler is always maintained at the minimum boiler temperature.
When using this setting, the boiler is operated at the minimum boiler temperature
whenever there is a heat request from one of the heat consumers. When there is no
heat request, the boiler temperature can drop below its minimum.
When using the “Summer“ setting, the boiler maintains the minimum temperature only if
the boiler sequence manager allows the boiler to run in summer operation.
The boiler also decides to run in summer operation if it did not receive a valid boiler
temperature setpoint from the boiler sequence manager for more than 72 hours, or if
the outside temperature exceeded a limit value.
7.9.6
Protection against boiler overtemperatures
To protect the boiler against overtemperatures on burner shutdown because there may
be no more consumers drawing heat, a consumer overrun time can be set for every
boiler.
Main menu > Commissioning > Settings > …
or
Main menu > Settings > Boiler … > Limitations
Operating line
Range
Factory setting
Consumer overrun time
0…60 min
6 min
After the burner has shut down, the overrun time ensures that the heating circuits and
DHW heating still draw heat for that period of time provided they were consuming heat
up to 1 minute before the burner was shut down. In any case, pumps and mixing valves
observe an overrun time of 60 seconds. For more detailed information, refer to section
5.4 “Pump overrun and mixing valve overrun”.
The overrun time also applies to the boiler pumps and shutoff valves (including the
mixing valve for the maintained boiler return temperature).
7.9.7
Pump kick and valve kick
The pump kick is a protective function that is carried out periodically. It prevents pumps
and/or valves from seizing after longer off periods. For more detailed information, refer
to section 5.5 “Pump kick and valve kick”.
7.9.8
Frost protection for the plant with boiler pump
Here, it can be selected whether frost protection for the plant shall act on the boiler
pump. For detailed information about frost protection for the plant, refer to section 5.3
“Frost protection for the plant”.
7.9.9
Frost protection for the boiler
Supervision of the boiler temperature prevents the boiler from freezing up.
When the boiler temperature drops below 5 °C, the burner is switched on; when it
returns to a level above SD (minimum boiler temperature plus switching
differential), the burner is switched off again.
Without boiler shutdown
Automatic boiler
shutdown
Summer