Viessmann Vitodens 050-W Installation And Service Instructions Manual page 38

Commissioning, inspection, maintenance
Adjusting the integral circulation pump rate
In the delivered condition, the minimum pump rate
■
and the maximum pump rate are set to the following
values:
Rated heating output
in kW
19
25
■ In the following system conditions, the internal circu-
lation pump is operated at a constant speed:
– Constant operation
Residual head of integral circulation pump
600 60
L
550 55
K
500 50
450 45
H
400 40
350 35
G
300 30
250 25
F
200 20
150 15
E
100 10
D
50
5
C
B
0 0
A
0 100 200
Flow rate in l/h
Fig. 26
Curve
A
B
C
D
E
F
G
H
K
L
38
Speed settings in the de-
livered condition in %
Min. pump Max. pump
rate rate
40 100
40 100
300 400 500 600 700
Pump rate of circulation pump
(cont.)
800 900 1000 1100 1200
10 %
20 %
30 %
40 %
50 %
60 %
70 %
80 %
90 %
100 %