Page 65 of 72
©Retrotec Inc. 2012
Appendix D: Adjust Flow values for temperature difference
Temperature correction is only required when there is a temperature difference between the area
under test, (inside), and the area used as reference for the test, (outside).
To use the tables, determine if you are pressurizing or pressurizing. When pressurizing, the air flow of
the fan will be toward the inside, and when depressurizing, the air flow will be toward the outside.
Choose the correction factor from Table 17 for the depressurize case or Table 18 for the pressurize
case based on the current inside and outside temperatures. Multiply the flow you measured by the
factor to get the air flow corrected for temperature difference.
Retrotec’s FanTestic software automatically corrects flow values for any temperature difference when
inside and outside temperatures are entered into the software.
Table 17: Temperature correction factors for enclosure DEPRESSURIZATION
50
55
60
65
70
75
80
85
90
-20
0.848
0.844
0.840
0.836
0.832
0.828
0.824
0.820
0.816
-15
0.857
0.853
0.849
0.845
0.841
0.837
0.833
0.829
0.826
-10
0.867
0.863
0.859
0.855
0.851
0.847
0.843
0.839
0.835
-5
0.877
0.872
0.868
0.864
0.860
0.856
0.852
0.848
0.844
0
0.886
0.882
0.878
0.874
0.869
0.865
0.861
0.857
0.854
5
0.896
0.892
0.887
0.883
0.879
0.875
0.871
0.867
0.863
10
0.906
0.901
0.897
0.893
0.888
0.884
0.880
0.876
0.872
15
0.915
0.911
0.906
0.902
0.898
0.894
0.890
0.885
0.881
20
0.925
0.920
0.916
0.912
0.907
0.903
0.899
0.895
0.891
25
0.935
0.930
0.926
0.921
0.917
0.912
0.908
0.904
0.900
30
0.944
0.940
0.935
0.931
0.926
0.922
0.918
0.913
0.909
35
0.954
0.949
0.945
0.940
0.936
0.931
0.927
0.923
0.919
40
0.964
0.959
0.954
0.950
0.945
0.941
0.936
0.932
0.928
45
0.973
0.968
0.964
0.959
0.955
0.950
0.946
0.941
0.937
50
0.983
0.978
0.973
0.969
0.964
0.960
0.955
0.951
0.946
55
0.992
0.988
0.983
0.978
0.974
0.969
0.964
0.960
0.956
60
1.002
0.997
0.992
0.988
0.983
0.978
0.974
0.969
0.965
65
1.012
1.007
1.002
0.997
0.992
0.988
0.983
0.979
0.974
70
1.021
1.016
1.011
1.007
1.002
0.997
0.993
0.988
0.983
75
1.031
1.026
1.021
1.016
1.011
1.007
1.002
0.997
0.993
80
1.041
1.036
1.031
1.026
1.021
1.016
1.011
1.007
1.002
85
1.050
1.045
1.040
1.035
1.030
1.025
1.021
1.016
1.011
90
1.060
1.055
1.050
1.045
1.040
1.035
1.030
1.025
1.021
95
1.070
1.064
1.059
1.054
1.049
1.044
1.039
1.035
1.030
100
1.079
1.074
1.069
1.064
1.059
1.054
1.049
1.044
1.039
105
1.089
1.084
1.078
1.073
1.068
1.063
1.058
1.053
1.048
110
1.098
1.093
1.088
1.083
1.078
1.073
1.068
1.063
1.058
Inside Temperature (F)
O
ut
s
ide
Te
m
pe
ra
ture
(
F)
