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Nothing is more important than air flow for the proper operation of a
clothes dryer. A dryer is a pump which draws make-up air from the
out-of-doors, through the heater, through the clothes and then forces
the air through the exhaust duct back to the out-of-doors. Just as in a
fluid water pump, there must be a fluid air flow to the inlet of the
dryer, if there is to be the proper fluid air flow out of the exhaust
duct.
In summary, there must be the proper size out-of-doors inlet air
opening (4-6 times the combined areas of the air outlet) and an
exhaust duct, size and length of which allows flow through the dryer
with no more than 0.3 inches water column (.8 mbar) static pressure
in the exhaust duct.
In some instances, special fans are required to supply make-up air,
and/or boost exhaust fans are required for both regular and energy
saving models.
FOR BEST DRYING:
1 .
Exhaust duct maximum length 14 feet (5 m) of straight duct
and maximum of two 90° bends.
2 .
Use 45° and 30° elbows wherever possible.
3 .
Exhaust each dryer separately.
4 .
Use 2 feet (0.6 m) of straight duct on dryer before installing
an elbow on Energy-Saver models only.
5 .
Do not
install wire mesh or other restrictions in the exhaust
duct.
6 .
Use clean-outs in the exhaust duct and clean periodically
when needed.
7 .
Never
exceed 0.3 inches water column (.8 mbar) static
pressure in the exhaust duct.
8.
Inside surface of the duct
must be smooth
.
9 .
Recommend pop rivets for duct assembly.
FOR BEST DRYING:
1 .
Provide opening to the out-of-doors in accordance with the
following:
For each dryer
—
6 inches (2 m) diameter exhaust requires a 1 square feet
(0.1 m²) opening for make-up air.
8 inches (3 m) diameter exhaust requires a 2 square feet
(0.2 m²)opening for make-up air.
12 inches (4 m) diameter exhaust requires a 4 square feet
(0.4 m²)opening for make-up air.
2.
Use barometric shutters in the inlet air opening to control air
when dryers are not running.
Other Recommendations
To assure compliance, consult local building code requirements.
T r o u b l e s h o o t i n g
Hot dryer surfaces, scorched clothes, slow drying, lint accumulations,
or air switch malfunction are indicators of exhaust duct and/or make-
up air problems.
Exhaust and Venting
DRYER AIR FLOW
INSTALLATION
EXHAUSTING
D U C T
MAKE-UP AIR
O T H E R
RECOMMENDATIONS
TROUBLESHOOTING
