5Design Informationclearances• The downdraft system with blower, motorand ductwork will occupy the cabinet belowthe countertop and cooktop.• The blower/motor assembly can be locatedbelow the cabinet floor. The assembly will fitbetween 16" floor joists. Order JXRB67 for indoorremote locations.• The blower motor assembly can also be installedoutdoors. Order JXBC67 for remote blowerinstallations outdoors.• Refer to Clearances for informationon appropriate placement and necessaryclearances when planning installation.• Refer to your specific cooktop installationinstruction for other appropriate clearances.• Avoid placing cabinetry directly abovethe cooking surface when possible.If cabinetry is used above the cooking surface:• Use cabinets no more than 13" deep.• Maintain 30" minimum clearance betweencooktop and unprotected cabinets directly abovecooktop.• If clearance is less than 30", protect cabinetbottoms with flame-retardant millboard at least1/4" thick or gypsum board at least 3/16" thickcovered with 28 gauge sheet steel or .02" thickcopper.• Clearance between cooktop and protectedcabinetry must not be less than 24".EXCEPTION: Installation of a listed microwaveoven or cooking appliance over the cooktop shallconform to the installation instructions packedwith that appliance.• Working areas adjacent to the cooktopshould have 18" minimum clearance betweencountertop and cabinet bottom.• Installation must conform with local codes.DuctworkPrepare ductwork to vent to the outdoors.• Use the shortest and straightest duct run possible.• The maximum permissible length for duct runis 150 feet.• Refer to “Duct Fittings” chart to calculateequivalent length for various duct configurations.• The downdraft blower system is designed to use3-1/4" x 10" ductwork. It can be transitioned to6" round.• Ductwork MUST be vented to the outside–neverinto 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 locationsPlan the placement of the electrical outlet and gasconnections (if used) carefully. Electrical outlets andgas connections cannot be placed on the back wallof the cabinet because it may interfere with thedowndraft plenum. Refer to POWER SUPPLY sectionfor information on location of electrical and gasconnections.• Install a standard electrical outlet within reach ofthe vent’s two-foot-long power cord.• The vent and a GE or Monogram gas cooktopcombination can operate from the same 120-voltstandard duplex outlet.• Electric cooktops must operate from a separate240-volt junction box.• A 90° elbow (not supplied) can be installed onto theinlet of the gas cooktop and route the gas connec-tions to avoid interference when installed with adowndraft vent or other cabinetry features.