GE JVB36 - Planing the Ductwork

Operating Instructions
10
Safety Instructions
Installation Instructions
Troubleshooting TipsCustomer Service
Installation of the downdraft system.
Read these instructions completely and carefully.
Planning the Ductwork
This downdraft blower system is designed
for use with 3
1
⁄
4
″ x 10″ ductwork (can be
transitioned to 6″ round). Two different
discharge directions are available with side-to-
side adjustment for accurate alignment of
ductwork.
For best performance: Choose the ducting
option which allows the shortest length of
ductwork and a minimum number of elbows
and transitions. Check location of floor joists,
wall joists, wall studs, electrical wiring or
plumbing for possible interference.
Steps to Determine Flexible Ducting’s Equivalent Length
Measure the actual amount of offset
(Maximum 3″ recommended). The effect
upon airflow is dependent upon the amount
of offset.
Calculate the equivalent ducting
allowances using:
( ___ in. offset) x (14 ft. per inch)
= ___ ft. equivalent length.
Ensure that the total equivalent length of
ducting does not exceed the maximum
recommendation of 150 feet.
Left discharge (as shipped)
Right discharge
Duct Equivalent Duct Equivalent Duct Equivalent
Pieces Length* Pieces Length* Pieces Length*
3
1
⁄
4
″ x 10″
to 6″ Round
6″ Round 1 ft. (per 3
1
⁄
4
″ x 10″ Transition
12 ft.
Straight foot length) 45° Elbow
5 ft.
90° Elbow
6″ Round
3
1
⁄
4
″ x 10″ 1 ft. (per 3
1
⁄
4
″ x 10″ Wall Cap 21 ft.
Straight foot length) 90° Flat Elbow
24 ft.
with Damper
6″ Round 3
1
⁄
4
″ x 10″
6″ 15 ft. to 3
1
⁄
4
″ x 10″ 7 ft. Wall Cap 27 ft.
90° Elbow Transition with Damper
3
1
⁄
4
″ x 10″
6″ to 6″ Round 5 ft. 6″ Round
45° Elbow
9 ft.
Transition Roof Cap
20 ft.
6″ Round
to 3
1
⁄
4
″ x 10″
3
1
⁄
4
″ x 10″ Transition
20 ft.
6″ Round
90° Elbow
16 ft.
90° Elbow Roof Vent
24 ft.
SHOULD NOT EXCEED 150 EQUIVALENT FT.
*Equivalent lengths of duct pieces are based on actual tests conducted by GE Evaluation Engineering
and reflect requirements for good venting performance. See chart for CFM Duct Length.