Retrotec DucTester 340 - Page 66

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©Retrotec 2017
Average Operating
Pressure (Pa)
Multiplier for
CFM25
55
1.60
60
1.69
65
1.77
70
1.85
75
1.93
80
2.01
85
2.08
90
2.16
95
2.23
100
2.30
105
2.37
110
2.43
115
2.50
120
2.56
125
2.63
130
2.69
135
2.75
140
2.81
145
2.87
150
2.93
155
2.99
160
3.05
165
3.10
170
3.16
175
3.21
180
3.27
185
3.32
190
3.38
195
3.43
200
3.48
When possible, use actual operating conditions to determine the best multiplier to use from the table
above.
Calculate a loss factor for supply and return leaks
Supply Loss Factor = (SLS x SLP x SPM)
Where: SLS is Supply Leakage Split (default 0.5)
SLP is Supply Leakage Penalty (default 1.0)
SPM is Supply Pressure Multiplier (default 1.0)
Supply Loss Factor = 0.5 * 1.0 * 1.0
= 0.5
Return Loss Factor = (RLS x RLP x RPM)
Where: RLS is Return Leakage Split (default 0.5)