78/226
Building Technologies
Boiler Sequence Controller RMK770
CE1P3132en
HVAC Products
6 Boiler sequence management
01.03.2005
Heat requisitions from other devices can be accepted via bus. In addition, 3 binary
inputs and 1 analog input are available for signaling heat requisitions.
6.3
Boiler sequence management
6.3.1 Concept
T
T
T
T
T
MnPu_A
TMnRt
TMnFl
MnVlvRtMx
TRtMx
TBo
T
TRtCo
MnPu_B
T
TBo
1
2
TFl
w
TFl
x
TBo2
w
TBo1
w
T
3132
S
6
0
With the signal received from the main flow temperature sensor, the boiler sequence
manager controls the individual boilers or burner stages of the boiler sequence. It de-
cides on the release of a boiler, predefines the boiler temperature setpoint for the boil-
ers released and, in addition, releases the individual burner stages depending on heat
demand.
Here, the boiler sequence manager differentiates between lead boiler and lag boilers.
The lead boiler is always the first boiler to be put into operation. It always maintains the
boiler temperature setpoint predefined by the boiler sequence manager. The boiler
temperature setpoint of the lead boiler is raised or lowered, depending on the deviation
of the temperature acquired by the main flow sensor from the setpoint. The setpoint
correction can be adjusted.
Main menu > Commissioning > Settings > …
or
Main menu > Settings >
Boiler sequence manager > Control parameters
Operating line
Range
Factory setting
Boiler setpoint boost max
0…100 K
10 K
An increase can be applied to the boiler temperature setpoint of the lag boilers.
Main menu > Commissioning > Settings > …
or
Main menu > Settings >
Boiler … > Operation settings
Operating line
Range
Factory setting
Setpoint increase lag boiler
0…50 K
10 K
A considerable increase of the boiler temperature setpoint ensures that the lead boiler
provides control and that the relevant lag boiler operates at full capacity. This approach
prevents several boilers with their burner stages from cycling simultaneously.
Heat requisition
Setting
Setting