| 9Installation InstructionsBosch 96% AFUE Condensing Gas Furnace - BTC 770503101 J (06.2023)Figure 3Clearance arrows do not change with furnace orientation1’’TOP/PLENUM0’’ BACK0’’ SIDESIDEMOTTOB0’’0’’3’’FRONTØSIDES* FRONT BACK TOP(PLENUM)0" 3" 0" 1"Minimum clearance from combustible constructionWhen the unit is installed in the horizontal orientation, there must be 7"clearance in order to install the externally mounted drain trap. If installed in an alcove or closet⌀ 24 inches is required for service and maintenance.Horizontal installation in attic or crawl spaceIndicates supply or return sides when furnace is in the horizontal position. Linecontact only permissible between lines formed by intersections of the side andback of the furnace cabinet and building joists, studs or frame.Horizontal applications require a solid, supportive structure for installation(refer to Section 7.2 “Horizontal Installation”).For upflow and horizontal applications, the furnace must be pitched a minimum of1/2" (12.7 mm) to a maximum of 3/4" (19 mm) forward for proper drainage.See Section 7, "Installation" of this manual for more information.Figure 41/2”~3/4”1/2”~3/4”4 Codes and StandardsFollow all national and local codes and standards in addition to these instructions.The installation must comply with regulations of the serving gas supplier, localbuilding, heating, plumbing, and other codes. In absence of local codes, theinstallation must comply with the national codes listed below and all authoritieshaving jurisdiction. Follow all codes and standards for the following:4.1 Safetyf US: National Fuel Gas Code (NFGC) NFPA 54-Latest/ANSI Z223.1-latest edition and the Installation Standards, Warm Air Heating and AirConditioning Systems ANSI/NFPA 90Bf CANADA: National Standard of Canada Natural Gas and PropaneInstallation Codes (CAN/CSA-B149.1-05)Figure 5Max 85°F/29°CMin 60°F/16°COUTLETAIRFRONTReturn Air Temperature4.2 General Installationf US: Current edition of the NFGC and the NFPA 90B. For copies,contact the National Fire Protection Association Inc., 1 BatterymarchPark, Quincy, MA 02169; (www.NFPA.org) or for only the NFGC,contact the American Gas Association, 400 North Capital Street, NW,Suite 450, Washington, DC 20001 (www.AGA.org)f CANADA: NSCNGPIC.For a copy,contact Standard Sales, CSAInternational,178 Rexdale Boulevard, Etobicoke (Toronto),Ontario,M9W 1R3 Canada