9. Horizontal furnace, with media air cleaner mounted vertically in return duct near furnace. M946A Fig. 10.Two or more media air cleaners used in a high capacity system. Determining Sheet Metal Requirements The media air cleaner is adaptable to all new or existing forced air heating and cooling systems used in residential applications. Transitions or turning vanes may be required in some applications for effective media air cleaner operation. Transitions Transitions are needed when the duct is a different size than the media air filter cabinet. Follow these guidelines when fabricating: 1. Use gradual transitions to reduce air turbulence and increase efficiency. See Fig. 11. 2. Use no more than 20 degrees (about 4 in. per running ft [100 mm per 300 linear mm]) of expansion on each side of a transition fitting. Turning Vanes If the media air cleaner is installed next to an elbow or angle fitting, add turning vanes inside the angle to distribute airflow more evenly across the face of the media. See Fig 12. Offsets If the duct connection to the furnace in a side installation allows less than 7 in. (178 mm) for mounting media air cleaner cabinet, attach an offset to the elbow. See Fig. 13. DUCT SIZE CHANGED GRADUALLY TO PREVENT TURBULENCE. 20 DEGREE EXPANSION PER SIDE PER FITTING (4 IN. PER RUNNING FOOT [100 MM PER 300 LINEAR MM]) RETURN AIR DUCT TRANSITION FITTING MEDIA AIR FILTER CABINET M947A Fig. 11. Duct size changed gradually to prevent turbulence. TURNING VANES M5651 Fig. 12.Turning vanes installed in bend help distribute airflow evenly over face of media. 68-0178—2 6 F35F Expandapac™ MEDIA AIR CLEANER LESS THAN 7 in. (178 mm) OFFSET AT LEAST 7 in. (178 mm) 1 1 REQUIRED TURNING VANES HELP DISTRIBUTE AIRFLOW EVENLY. F35F Expandapac™ MEDIA AIR CLEANER LESS THAN 7 in. (178 mm) OFFSET AT LEAST 7 in. (178 mm) 1 1 REQUIRED TURNING VANES HELP DISTRIBUTE AIRFLOW EVENLY. M948A Fig. 13. Typical use of duct offset to make room for media air cleaner. INSTALLATION AND CHECKOUT When Installing this Product… 1. Read these instructions carefully. Failure to follow them could damage the media air cleaner or cause a hazardous condition. 2. Check the ratings given in the instructions and on the media air cleaner to make sure the product is suitable for your application. 3. Installer must be a trained, experienced service technician. Remove Furnace Filter and Clean Blower Compartment Before starting the installation, remove and discard the existing furnace filter (if used). Thoroughly clean the blower compartment. If possible, power vacuum the ductwork to remove accumulated dust in an occupied home or remove construction dirt in a new home. The media air filter cannot remove dirt that has settled in the blower compartment and distribution ducts. Install the Cabinet The following procedure describes a typical side installation on an existing highboy furnace. Alternate procedures are noted as appropriate. Other changes in installation procedures may be necessary to complete your installation. Review the Installation Plan Temporarily place the cabinet on the floor, oriented as it will be when installed. Measure to make sure the plan allows adequate clearance (at least 26 in. [660 mm]) for easy removal and replacement of the filter. Make sure that shop-fabricated sheet metal components, such as turning vanes, are available. Fasten the Cabinet to the Furnace Align the cabinet with the return air opening. Place blocks under the cabinet, as necessary, to make sure the unit is seated securely. Create an opening in the furnace to match the cabinet opening. Attach the cabinet securely to the furnace. Attach the unit directly or fit a starting collar in the furnace opening. Either drill holes and fasten with sheet metal screws or rivets, or use slip joints. If you are drilling holes, use a locking pliers to help hold the unit in place during drilling. Install Turning Vanes Install turning vanes to help distribute air equally over the full surface of the upstream side of the media. Install the vanes whenever an abrupt 90 degree elbow is installed directly against the media air cleaner cabinet. Fasten Cabinet to Ductwork Fasten the side of the cabinet to the ductwork using sheet metal screws, rivets, or slip joints, as appropriate. Connect Ductwork Connect the vertical duct section to the elbow. If the vertical drop of the duct is less than 7 in. (178 mm) from the side of the furnace, shorten the horizontal trunk or attach an offset fitting to the elbow. See Fig. 13. When ductwork is properly aligned, connect the vertical duct to the horizontal trunk. Seal Joints Seal all joints in the return air system between the media air cleaner and the furnace to prevent dust from entering the clean airstream. Assemble Expandapac Media Filter 1. Open the new media filter; expand it and set it upright on a flat surface. 2. Insert one end panel tab into the retainers on the frame. Fold in the end panel flanges and push the tab completely in, making s...