11
20152093
GB
Technical description of the burner
4.7.1
Firing rate according to air density
The burner firing rate specified in the manual applies for an
ambient temperature of 20 °C and an altitude of 0 m a.s.l.
(barometric pressure of approx. 1013 mbar).
The burner may have to operate at a higher altitude and/or with
combustion air at a higher temperature.
Both air heating and increased altitude cause air volume
expansion, i.e. air density is reduced.
Burner fan flow rate remains basically the same but oxygen
content per cu. m of air is reduced as well as the fan push (head).
Therefore, it is important to know whether burner required
maximum output at a certain pressure in the combustion
chamber remains within the burner firing rate also under different
temperature and altitude conditions.
To check this, proceed as follows:
1
find the correction factor F concerning air temperature and
altitude for the system in Tab. F.
2
Divide output Q requested from the burner by F to obtain the
equivalent output Qe:
3
Within burner firing rate, mark the point identified by:
Qe = equivalent output
H1= pressure in combustion chamber
point A that must remain within the firing rate.
4
Draw a vertical line from point A)(Fig. 3), and calculate the
maximum pressure H2 of the firing rate.
5
Multiply H2 by F to obtain the reduced maximum pressure
H3 of the firing rate:
If H3 is higher than H1)(Fig. 3), the burner can output the
requested flow rate.
If H3 is lower than H1, burner output must be reduced. Output
reduction is also combined with a reduction of the pressure in the
combustion chamber:
Qr = reduced output
H1r = reduced pressure
Example, 5% output reduction:
Qr = Q x 0.95
H1r = H1 x (0.95)2
Using the new Qr and H1r values, repeat steps 2-5.
Tab. F
Qe = Q : F (kW)
H3 = H2 x F (mbar)
ATTENTION
The combustion head must be adjusted according
to equivalent output Qe.
H1r = H1 x
( )
Qr
Q
2
Qe
kg/h
mbar
Qe
kW
mbar
A
H1
H2
H3
D388
Fig. 3
Altitude
Average
barometric
pressure
F
Air temperature °C
m a.s.l.
mbar
0
5
10
15
20
25
30
40
0
100
200
300
400
500
600
700
800
900
1000
1200
1400
1600
1800
2000
2400
2800
3200
3600
4000
1013
1000
989
978
966
955
944
932
921
910
898
878
856
836
815
794
755
714
675
635
616
1.087
1.073
1.061
1.050
1.037
1.025
1.013
1.000
0.988
0.977
0.964
0.942
0.919
0.897
0.875
0.852
0.810
0.766
0.724
0.682
0.661
1.068
1.054
1.042
1.031
1.018
1.007
0.995
0.982
0.971
0.959
0.946
0.925
0.902
0.881
0.859
0.837
0.796
0.753
0.711
0.669
0.649
1.049
1.035
1.024
1.013
1.000
0.989
0.977
0.965
0.954
0.942
0.930
0.909
0.886
0.866
0.844
0.822
0.782
0.739
0.699
0.657
0.638
1.031
1.017
1.006
0.995
0.983
0.972
0.960
0.948
0.937
0.926
0.914
0.893
0.871
0.851
0.829
0.808
0.768
0.726
0.687
0.646
0.627
1.013
1.000
0.989
0.978
0.966
0.955
0.944
0.932
0.921
0.910
0.898
0.878
0.856
0.836
0.815
0.794
0.755
0.714
0.675
0.635
0.616
0.996
0.983
0.972
0.962
0.950
0.939
0.928
0.916
0.906
0.895
0.883
0.863
0.842
0.822
0.801
0.781
0.742
0.702
0.664
0.624
0.606
0.980
0.967
0.956
0.946
0.934
0.923
0.913
0.901
0.891
0.880
0.868
0.849
0.828
0.808
0.788
0.768
0.730
0.690
0.653
0.614
0.596
0.948
0.936
0.926
0.916
0.904
0.894
0.884
0.872
0.862
0.852
0.841
0.822
0.801
0.783
0.763
0.743
0.707
0.668
0.632
0.594
0.577
Summary of Contents for RS 200/M BLU
Page 2: ...Translation of the original instructions ...
Page 51: ...49 20152093 GB Appendix Electrical panel layout 0 ...
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