Miele T 80 Series Technical Information page 66

Technical Information
4" flexible aluminum ducting can be used as an upgrade from the foil
ducting. This duct will flow more air, so the noise will be reduced (but not
eliminated). When installed correctly, the flexible aluminum ducting will not
move when the dryer is operating. This stability also helps to decrease the
noise of the exhaust airflow. The less bends and kinks that exist, the quieter
it will be. This ducting is better than the previous ducting due to reduced
noise in the dryer and sturdy construction. Because of this sturdier
construction, the installation of this ducting may be slightly more difficult.
4" Solid Ducting
4" solid ducting offers the best sound reduction of all 4" choices. It is not
hard to install, but the ability to install it in each situation must be investigated.
It will not fit inside a standard 2" x 4'' wall, so it is limited to external
installations or installations in concealed spaces. The turbulence of the air
flow is almost unnoticeable with solid ducting.
More efficient at
exhausting heat
Benefits
Best noise reduction
Most efficient at
exhausting heat
66
T 80xx
Slightly more
expensive
Limitations
Difficult installation. Will not
fit inside of a 2"x 4" wall
Non-flexible
More expensive & may
require professional
installation