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- Always keep the duct clean to ensure proper airflow.
- It is recommended that the range hood be vented vertically through
the roof through 6” (15.2 cm) round metal/aluminium vent work. The
size of the vent should be uniform.
- Use no more than three 90
o
elbows and do Not install two elbows
together.
- Make sure there is a minimum of 24”(61cm) of straight vent between
the elbows if more than one elbow is used. The length of vent system
and number of elbows should be kept to a minimum to provide efficient
performance.
- The vent system must have a damper. If roof or wall cap has a damper,
Do Not use damper supplied with the range hood.
- Use duct tape to seal all joints in the vent system.
- Fasten all connections with sheet metal screws and tape all joints with
certified Silver Tape or Duct Tape.
Calculate the duct run length:
If ducted with the required minimum of 6” round duct work, the duct run
should not exceed 35 equivalent feet. Calculate the length of the duct
work by adding the equivalent feet as below for each piece of duct in the
system.
If you must elbow right away, do it as far away from the hood’s exhaust
opening as possible.
45
o
Elbow - 3.0 feet
90
o
Elbow - 5.0 feet
90
o
Flat Elbow - 12.0 feet
Wall Cap - 0.0 feet
9 Feet Straight Duct 9.0 feet
2-90
o
Elbow 10.0 feet
Wall Cap 0.0 feet
Total System 19.0 feet