5
Design Information
clearances
• The downdraft system with blower, motor
and ductwork will occupy the cabinet below
the countertop and cooktop.
• The blower/motor assembly can be located
below the cabinet floor. The assembly will fit
between 16" floor joists. Order JXRB67 for indoor
remote locations.
• The blower motor assembly can also be installed
outdoors. Order JXBC67 for remote blower
installations outdoors.
• Refer to
Clearances
for information
on appropriate placement and necessary
clearances when planning installation.
• Refer to your specific cooktop installation
instruction for other appropriate clearances.
• Avoid placing cabinetry directly above
the cooking surface when possible.
If cabinetry is used above the cooking surface:
• Use cabinets no more than 13" deep.
• Maintain 30" minimum clearance between
cooktop and unprotected cabinets directly above
cooktop.
• If clearance is less than 30", protect cabinet
bottoms with flame-retardant millboard at least
1/4" thick or gypsum board at least 3/16" thick
covered with 28 gauge sheet steel or .02" thick
copper.
• Clearance between cooktop and protected
cabinetry must not be less than 24".
EXCEPTION: Installation of a listed microwave
oven or cooking appliance over the cooktop shall
conform to the installation instructions packed
with that appliance.
• Working areas adjacent to the cooktop
should have 18" minimum clearance between
countertop and cabinet bottom.
• Installation must conform with local codes.
Ductwork
Prepare ductwork to vent to the outdoors.
• Use the shortest and straightest duct run possible.
• The maximum permissible length for duct run
is 150 feet.
• Refer to “Duct Fittings” chart to calculate
equivalent length for various duct configurations.
• The downdraft blower system is designed to use
3-1/4" x 10" ductwork. It can be transitioned to
6" round.
• Ductwork MUST be vented to the outside–never
into a crawl space, attic or other enclosed space.
• Determine the need for a wall cap or roof cap.
Order the cap in advance.
electrical and Gas locations
Plan the placement of the electrical outlet and gas
(if used) carefully. Gas or electrical outlets cannot
be placed on the back wall of the cabinet because
it may interfere with the downdraft plenum.
• Install a standard electrical outlet within reach
of the vent’s two-foot-long power cord.
• The vent and a GE or Monogram gas cooktop
combination can operate from the same 120-volt
standard duplex outlet.
• Electric cooktops must operate from a separate
240-volt junction box.