NuTone QTXEN - Manual (Page 6)

NuTone Ventilation Fans—Installation Guide
Proper installation makes all the difference.
Tape or caulk around the seam
where the fan housing meets
the sheetrock on the ceiling.
If possible, use smooth, rigid ductwork
as large as the exit opening on the
body of the fan housing.
During installation, orient the bath fan
outlet in the direction of the home’s
exit point to minimize duct turns.
Before adding an elbow or bend,
allow 24" to 36" of straight run from
the fan outlet point.
Duct-wrap insulation (R-5 or above)
will help minimize condensation in cold
climates, especially on long duct runs.
Whether rigid or flexduct,
the turning radius for the duct
should be as large as possible.
Whenever possible, ductwork should slope
down and away from the fan housing to
direct any condensation toward the vent.
Exit vents should have backdraft
flaps to help keep cold air from
entering the duct.
Quick guideline: For bathrooms up to
100 square feet, the HVI recommends
ventilation of about 1 CFM per square
foot (about eight air changes per
hour). For bathrooms over 100 square
feet, add up the needs of each fixture
to determine the total ventilation rate:
• Toilet 50 CFM
• Shower 50 CFM
• Bathtub 50 CFM
• Jetted tub 100 CFM
Keyhole slots and alignment tabs
facilitate installation, taking the
guesswork out of proper mounting.
Elbows, turns, long ducts and
ductwork smaller than the fan’s exit
outlet will reduce performance.
Use wide aluminum foil or duct tape to
join smooth metal ductwork seams.
Do not let flexible ductwork sag as this
impedes airflow.
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