Bard Bayrd Furnace 403293A - Manual (Page 24)

EXTERNAL STATIC PRESSURE
(Inches of Water Column)
"INPUT
(BTU/HR)
MINIMUM MAXIMUM
40,000 0.10 0.50
60,000 0.12 0.50
80,000 0.12 0.50
100,000 0.15 0.50
120,000 0.20 0.50
140,000 0.20 0.50
‘Input is on furnace rating plate on blower door.
FIGURE 24
A. Supply air duct work.
NOTE: Supply air duct (plenum) connection must be the
same size as the furnace supply air opening. Attach to
furnace duct flanges.
If you install furnace in horizontal position with an air
conditioner, design a minimum 18" long transition that
allows free air flow through furnace and cooling coil. Make
sure furnace temperature rise is within range noted on
furnace rating plate. Also, consult air conditioner's duct
work installation Instructions.
Seal supply air duct work to furnace casing, walls, ceilings
or fioors it passes through. End duct work outside furnace
space.
B, Return air duct work.
1. In upflow position, return air duct must be a mini­
mum depth of 23-31/32". See Figure 25.
2. In downflow position, return air duct must be a mini­
mum 19-7/8" inside depth. See Figure 26.
CASING
WIDTH
14.50
20.50
23.50
FIGURE 25
NOTE: In upflow position, if bottom return air is not
used, you must attach a solid bottom closure panel
to bottom return air opening. Bottom closure panel is
available from manufacturer as follows:
BTU/HR" MOTOR* BOTTOM CLOSURE
INPUT H.P. PART NUMBER
40,000 1/4
40,000 1/3 4045900
60,000 1/4
60,000 1/3
60,000 1/2 4045901
80,000 1/4 4045900
80,000 1/3
80,000 1/2 4045901
80,000 3/4 4045902
100,000 1/3 4045901
100,000 1/2
100,000 3/4
120,000 1/2 4045902
120,000 3/4
140,000 3/4 4045903
140,000 3/4
"See furnace rating plate on blower door.
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