Honeywell EXPANDAPAC F35F - Manual (Page 6)

F35F Expandapac™ MEDIA AIR CLEANER
68-0178—2 6
M945A
M946A
Fig. 9. Horizontal furnace, with media air cleaner mounted
vertically in return duct near furnace.
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.
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
DUCT SIZE CHANGED GRADUALLY TO PREVENT TURBULENCE.
Fig. 12. Turning vanes installed in bend help
distribute airflow evenly over face of media.
TURNING
VANES
M5651
Fig. 11. Duct size changed gradually
to prevent turbulence.