Carrier 38GJQ Series Installation Instructions Manual

Also see for 38GJQ Series: Owner's manual

32Install the Round Air Supply Duct12435 6 78 9Fig. 51 – Air supply ductTable 38—Air DuctNO. NAME NO. NAME1 Return Air Duct 6 Transition Duct2 Canvas Duct 7 Air Supply Duct3 Return Air Louver 8 Diffuser4 Hanger 9 Diffuser Joint5 Air Supply DuctRound Air Supply Duct Installation1 Pre−install the round duct outlet on the transition duct andthen secure it with the tapping screw.2 Place the transition duct to the air outlet of the unit andsecure it with a rivet.3 Connect the outlet to the duct and then tighten them withtape.CAUTION!The max. length of the duct means the max. length of the airsupply duct plus the max. length of the return air duct.The duct is either rectangular or round and connected withthe air inlet/outlet of the indoor unit. Among all air supplyoutlets, at least one should remain open. As for the roundduct, it needs a transition duct of which should match the airsupply size of the unit.After fitting the transition duct, it is best to keep the roundduct 32ft. (10m) away from the corresponding diffuser.Air Supply Outlet and Return Air Inlet Drawings21ABFig. 52 – Air Supply OutletDCFig. 53 – Return Air InletTable 39—Dimensions of the Air Supply Outlet and ReturnAir Inlet (unit: in/mm)ITEM AIR SUPPLY OUTLET RETURN AIR INLETSize A B C D09 6 1/7 in(156 mm)26 in(662 mm)22 5/6 in(580 mm)22 5/6 in(580 mm)1218 6 1/7 in(156 mm)34 in(862 mm)30 5/7 in(780 mm)6 3/8 in(162 mm)21 6 1/7 in(156 mm)41 4/5 in(1062 mm)38 4/7 in(980 mm)6 3/8 in(162 mm)24Return Air Duct Installation1 The default installation location of the rectangular flange isin the back and the return air cover plate is in the bottom(see Fig. 54).Return Air Cover PlateDownward Return AirBackward Return AirRectangular FlangeFig. 54 – Return Air Duct2 If the downward return air is desired, just change the placeof the rectangular flange and the return air cover plate.3 Connect one end of the return air duct to the return air outletof the unit by rivets and the other to the return air louver.For the sake of the convenience, to freely adjust the height,a cutting of the canvas duct will be helpful, which can bereinforced and folded by 8# iron wire.4 More noise is likely to be produced in the downward returnair mode than the backward return air mode. We suggestinstalling a muffler and a plenum box to minimize the noise.5 The installation method can be chosen after considering theconditions of the building and maintenance etc. (see Fig. 55).1Wind supplyBack windInstall the back wind pipe (a)Wind supplyInstall the back wind pipe(b)Back wind12453645Fig. 55 – Return Air DuctTable 40—Air DuctNO. NAME NO. NAME1 Return Air Louver(with the filter screen) 4 Indoor Unit2 Canvas Duct 5 Air Supply Duct3 Return Air Duct 6 Access Grille