Retrotec DucTester 341 - Manual (Page 21)

Page 21 of 83
©Retrotec Inc. 2014
5.3 Flex Duct
Retrotec's duct testing systems US341 and EU341 include a 10" diameter, 12' long flexible duct to
connect the fan to a register, or duct system. A durable plastic Flange on one end is taped to a register
or air handler, and connected to the Flex Duct to ensure a strong and simple seal. Velcro straps on
either end securely attach the Flex Duct to the Flange and fan inlet or outlet.
Figure 8: Flex Duct for duct testing system with Flange and strap.
5.4 Additional included duct testing components
In addition to the calibrated fan and digital dual-channel pressure gauge, a Retrotec DucTester system
includes a few additional items.
5.4.1. Grill Mask for sealing registers
Grill Mask is used to seal over registers and vents. Grill Mask comes in a 12" wide roll.
It is perforated at 12" intervals to provide easy-to-tear pieces that can seal nearly
anything. Be careful applying Grill Mask to painted surfaces, as paint can be pulled off
when removing it after testing. Additional Grill Mask can be ordered from Retrotec as a
single roll or in three roll bundles. A handy Grill Mask dispenser is also available as an
optional accessory.
5.4.2. Umbilical for connecting fan and DM32 gauge
An umbilical neatly bundles the needed pressure tubes and Control Cable, to prevent
the user from being greeted by a tangled mess of tubes and cables before each test.
The standard 20' long DucTester umbilical includes a yellow, green, and blue
pressure tube, as well as the Control Cable used for the DM32 to communicate with
the fan. For detailed instructions on how to connect the DucTester fan and the
DM32 gauge using the Umbilical, refer to section 6.1.
5.4.3. Flange for connecting flex to ductwork at register
The Flange is the intermediate part used to secure the Flex Duct onto a return
register by using masking tape or Grill Mask. For instructions on how the Flange is
connected, refer to section 6.6.