Connecting The Ducts To The Unit - Broan B180H75rT User's And Installer's Manual

2.5 c D
onnecting the ucts to the
• If ducts have to go through an unconditioned space (e.g.: attic), always use insulated ducts to prevent condensation formation inside
and outside ducts, which could cause material damage and/or mold growth.
• Do not use screws to connect the ducts or transitions to the ports so as not to interfere with ports inner dampers operation. A
non-functioning damper could freeze the unit, which could cause damages.
i
nSulaTed flexiBle ducTS
Use the following procedure to connect the insulated flexible ducts to the ports of the unit (exhaust to outside and fresh air from outside).
1. Expose the flexible duct by pulling back the insulation, and place it over the inner port ring.
2. Attach the flexible duct to the port using a tie wrap.
3. Seal the joint using duct tape.
4. Pull the insulation and vapor barrier over the joint, tuck them between the inner and outer rings of the double collar and fasten them
in place using duct tape.
The vapor barrier should remain intact and free of cracks or openings. An opening could produce condensation inside or outside duct,
which could cause material damage and/or mold growth in the long run.
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ranSiTioning To in ducTS
If using 8-in. ducts, install 6-in. to 8-in. transitions on the ports, and secure using duct tape only. If rigid ducting is used, install a 12-in.
section of flexible duct between the transition and the rigid ducting (see above).
r
igid ducTS
To prevent potential water leakage in cold side rigid ducting insulation, seal all rigid ducting joints with duct tape.
To avoid transmission of vibrations, always use a 12-inch section of flexible duct to connect rigid ducts to the unit. To connect insulated
rigid ducts to the unit (cold side) using insulated flexible ducts, follow instructions in section 2.4. To connect regular rigid ducts (warm
side) to the unit using non-insulated flexible ducts, use a tie wrap.
NOTE: It is recommended to use 8" ducting instead of 6" ducting if required airflow is over 200 CFM and long run of ducting or
high quantity of elbows is used. It will prevent having too high static pressure in the ducting.
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CAUTION
CAUTION
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