Retrotec Commercial 441 and 451 DucTester - Manual (Page 26)

Page 26 of 56
©Retrotec Inc. 2015
5.6 Step 6 – Measure the Leakage
[Set Speed] to 1% then
Jog up to the Test
Pressure. WARNING: To prevent over-pressurizing, slowly increase fan speed
using Set Speed. Jog the speed up 1% at a time until a CFM value
appears on the display. Continue to increase fan speed up to but do
not exceed the Pressure Class. If you do not reach the Pressure
Class, results will still be calculated at for that Pressure Class.
Tap “@” on the display
to get flow at the
Default pressure set
earlier.
Results are displayed
displayed in any units.
Passes if value is lower
than that specified
The Leakage Factor, F is displayed as:
If this Leakage Factor is lower than or equal to the value specified,
the duct is in compliance. If it fails, measure Leakage Class per
section below.
5.7 Step 7 – Test Passes
Complete the test reports and, if required, obtain witness’s signature. Use Retrotec’s FanTestic
Software to generate a report automatically. You can edit a template to add logos and other details
that will print out each time you complete a test. In minutes.
Remove temporary blanks and seals. Restore ducts to pre-test conditions after testing is complete.
Notice the conditions in the building upon arrival and be sure to restore it to that condition before
leaving.
5.8 If test fails
If you can create on 0.1 In WC (25 Pa) the DM32 or the software will still give an accurate result. There
is usually no need to achieve the test pressure if the ducts will still fail. First check all seals and
connections for leaks. Use a positive pressure and survey all sections of ducts with your hands if you
have access. To increase the sensitivity, wet your hands. If ductwork is hard to reach, you can use
smoke inside the duct to locate the leak but this can be messy.
If it fails, additional sealing is needed .