Forno 312265136, Instruction Manual

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NEVER exhaust air or terminate duct work into spaces between walls, crawl spaces, ceiling, attics or garages.
All exhausts must be ducted to the outside.
Use metal ductwork only.
Fasten all connections with sheet metal screws and tape all joints with certified Silver Tape or Duct
Tape.
Duct Run Calculation:
Maximum run 6” or 3-1/4 x 10” duct 100FT
Deduct:
each 90 Elbow used 15FT
each 45 Elbow used 9FT
each 6” to 3-1/4 x 10” 1FT
transition used
each 3-1/4 x 10” to 6” 5FT
transition used
Side Wall Cap w/ damper 30FT
Roof Cap 30FT
e.g. – 1 roof cap, 2x90 elbows, 1x45 elbow
= 30’ + 30’ + 9’=69’ used,
31’ available for straight duct runs
DUCT SIZE
A minimum of 6” round duct must be used to
maintain maximum airflow efficiency.
Flexible ducts are provided for convenience, always
use rigid type metal ducts if available to maximize
airflow.
Also use calculation (on left) to calculate total
available duct run when using elbows, transitions
and caps.
ALWAYS, when possible, reduce the number of
transitions and turns. If required for a long duct,
increase duct size from 6” to 7 or 8”.
If a reducer is used, install a long reducer instead of
pancake reducer. Reduce duct size as far away from
opening as possible.
If turns or transitions are required: Install as far away
from opening and as far apart between pieces as
possible.
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