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Building Technologies
Boiler Sequence Controller RMK770
CE1P3132en
HVAC Products
6 Boiler sequence management
23.04.2009
Boiler sequence with 4 boilers and 2-stage burners as an example. Lag boilers with
great setpoint increase.
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31
32D
01
Heat demand or load
B
o
il
e
r 1
B
o
ile
r 2
B
o
ile
r 3
Bo
il
e
r 4
Burner stage in continuous operation
Burner stage cycling
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 great setpoint increase (to be set separately on each boiler) allows the lead boiler to
provide control while the relevant lag boiler operates at full capacity. This way, it is
made certain that several boilers with their burner stages do not cycle simultaneously.
With a small setpoint increase, or no increase at all, the relevant lag boiler also pro-
vides control. This can be especially desirable in the case of boiler sequences with
several modulating burners.
Boiler sequence with 4 boilers and modulating burners as an example.
Lag boilers with small setpoint increase or no increase at all.
0
20
40
60
80
100
120
140
160
180
200
220
240
260
280
300
320
340
360
380
400
0
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3132D
02
Heat demand or load
B
o
il
e
r
1
B
o
ile
r 2
B
o
ile
r 3
B
o
ile
r 4
Burner stage modulating
In the case of boilers with greatly different capacities (e.g. second boiler twice the
capacity of the first boiler), the second boiler can be put into operation after the first
boiler and the first boiler is shut down. The first boiler resumes operation only when
both stages of the second boiler are on. This ensures a better graduation of the total
boiler output.
Example
Example
Binary switching on
