Form I-RA/D 140/235 (Version A), Mfg No. 110318 Rev 4, Page 17
Installing
Ducts
Inlet Air Duct
Canadian installations require
field installation of an inlet air duct
(return air system) on a Model RAD heater. The blower-equipped
heater has an inlet air duct flange. Inlet duct dimensions (inside)
are:
Duct Flange
RAD140
RAD235
Height
32-1/8” (816mm)
32-1/8” (816mm)
Width
21-3/4” (552mm)
31-1/8” (791mm)
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RAD
A
Minimum B
140
30” (762mm)
15” (381mm)
235
40” (1016mm)
20” (508mm)
Model RAD
140
235
CFM (free air)
2000
3200
Air throw (9ft
suspension)
50 ft
65 ft
15M
20M
CFM .25" ESP 1425
2140
Slip the ductwork over the flange and attach using 1/2” long sheet
metal screws.
Discharge Duct
A discharge duct
may be
attached to a Model RAD heater. To con-
nect the duct to the heater,
• Remove the louvers from the furnace.
• Field fabricate a duct transition as illustrated.
• Attach duct transition to the heater using 1/2” long sheet
metal screws
IMPORTANT: Never reduce the furnace opening
size abruptly. Always use a tapered transition like
the one illustrated.
