Spreadsheet will calculate cost of duct leakage, Of duct leakage to outdoors, 8 spreadsheet will calculate cost of duct leakage – Retrotec DucTester 341 User Manual
Page 51
Page 51 of 83
©Retrotec Inc. 2014
10.7.3.
Convert “Flow/Area” data so it can be entered into spreadsheet
Before obtaining the Duct Leakage Test Reporting software, you may have previously only recorded the
“Flow/Area” data directly from your gauge, but no “Flow” data. Now you might like to print a report
based on this Flow/Area. You will soon realize that you cannot enter Flow/Area data directly into the
software to obtain results. Instead, you must enter “Flow” to calculate results; therefore, you must
calculate a “Flow” to enter.
Example:
You live in North Carolina, and your state code requires that you report your results in the units of
CFM/100 sq ft. During a prior test of your client’s duct system, you measured and recorded a Flow/Area
of 26.3 CFM/100 sq ft at 25.0 Pa on your gauge. The conditioned flow area of the house is 1500 sq ft.
What do you enter into the software as your “Flow”?
Flow =
Flow
Area
∗ conditioned floor area
Flow =
26.3 CFM
100 sq ft
∗ 1500 sq ft
Flow = 395 CFM
You would enter a “Flow” of 395 CFM, at a “Duct Pressure” of 25 Pa, with a “Conditioned Floor Area” of
1500 sq ft into the software.
10.8
Spreadsheet will calculate Cost of Duct Leakage
Values for parameters can be entered into the “Cost of Duct Leakage” section so that estimates of the
Annual Cooling Loss and Annual Heating Loss (i.e., potential energy losses due to duct leakage) can be
reported. These inputs are optional. If nothing is entered into this section, the “Cost of Duct Leakage”
section of the report will not appear in the output.
For further detail on Duct system loss parameter calculations, refer to section 13.
If you are unsure of what the values are, simply assume the default values by clicking the "Use Default
Values" button:
Note: The "Annual Cooling Loss" and "Annual Heating Loss" in the Duct Leakage Report are for
estimation purposes only.
10.8.1.
% of Duct Leakage to Outdoors
Enter the estimated percentage of the Total Duct leakage that leads to outdoors in order to estimate
Cost of Duct Leakage. (Input is only required when performing a Total Duct Leakage test)