GE JVB36 Owner's Manual page 30

Installation of the downdrafl system.
Read these instructions completely and carefully.
Planning the Ductwork
[] This downdrafl Uower system is designed
for use _dfl_ 3/i" x 10" (h_dwork (cm_be
mmsifi(med to 6' _ound). Two diffe_ em
discharge (]i_Te(:tions ave mailable xdd_ sMeqo-
side a({iusmmm _br accurate alignment of
Steps to DetermineFlexible Ducting's Equivalent Length
]
Measme the a(mal amom_t of()f_set
(Maximum 3" re(ommended). The effect
upol_ airflow is dependent upon d_e amomu
of of_get.
[]
[]
Calculate die equivalent duding
allo_%inces using:
( __ h-l.o*_se0 x (14ft. per inch)
=__ tL e(pfi_ alent length.
Ensme diat die total e(lui_ alem lengd_ of
(]u(ting does not ex(eed the maximum
recommendation o_ 150 f>et.
Rightdis/barge
[]
For best perfo_nm'_ee: ( hoose file ducd_lg
option which allows d_e shortest lengfli of
dudwo_ k and a minimum mm_be_ of elbows
and transitions. Check location offiooLjoists,
waffjoists, wall studs, de( tvical _dring ov
plumbing fi, possibD int err>fence.
3X" x 10"
to 6" Round
Transition
90° Elbow
12 ft.
6" Round 1 ft. (per 35" x 10" 5 ft.
Straight foot length) 45° Elbow
0" Round
37F x 10" 1 ft. (per 37F x 10" Wall Cap 21 ft.
Straight foot length) 90° Flat Elbow 24 ft. with Damper
(_ _ 0" Round 35" x 10"
6" 15 ft. to 3Y/' x 10" 7 ft. Wall Cap 27 ft.
90° Elbow Transition with Damper
_ 3W' x 10"
0" to 6" Round 5 ft. 0" Round
45° Elbow 9 ft. Transition Roof Cap 20 ft.
0" Round
to 3Y/' x 10"
374"x 10" Transition 20 ft. 0" Round
90° Elbow 10 ft. 90° Elbow Roof Vent 24 ft.
SHOULDNOT EXCEED150EOU/VALENTFT.
*Equivalent lengths of duct pieces are based on actual tests conducted by GEEvaluation Engineering
and reflect requirements for good venting performance. See chart for CFM Duct Length.
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