AAON SA-070 - Manual (Page 36)

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Example:
A total of 8 wires must be pulled 75ft to a
control the unit. What size wire should be
used?
According to the Table 5, 16 AWG allows
for 63ft (500 ft/8 wires) and 14 AWG allows
for 94ft (750 ft/8 wires). Thus, 14 AWG
should be used.
Duct Connection
Return air enters the either the left, right or
both the left and right sides of the unit,
where the air filters are located. Ductwork
should be sized in accordance with the
ASHRAE Handbook. Ductwork should be
installed in accordance with NFPA Standard
90A.
When attaching duct to the unit, use a
flexible/compressible material rated for duct
connections. A three inch flexible connector
for both return and supply duct connections
is recommended.
Supply air duct connection can be on the
left, right, back, or top sides of the supply
fan plenum. See unit drawing for more
information.
Table 6 - Duct Connection Sizes
Location
Model (SA-)
023-025 045-070
Top
30” x 64” (2) 30” x 64”
Back
19” x 30” (2) 19” x 30”
Side
(Right or Left)
19” x 64” (2) 19” x 64”
Condensate Drain Piping
Unit may be equipped with more than one
condensate drain pan connection. A p-trap
and drain line must be installed on every
drain connection, with the p-trap not to
exceed 6” from the drain connection. The
lines should be the same pipe size or larger
than the drain connection, include a p-trap,
and pitch downward toward drain. An air
break should be used with long runs of
condensate lines.
Draw-through cooling coils will have a
negative static pressure in the drain pan area.
This will cause an un-trapped drain to back
up due to air being pulled up through the
condensate drain piping.
Condensate drain trapping and piping should
conform to all applicable governing codes.
Note: The drain pan connection is a 1” MPT
fitting.
Figure 11 - Drain Trap
The X dimension on the draw-through trap
should be at least equal to the absolute value
of the negative static pressure in the drain
pan plus one inch. To calculate the static
pressure at the drain pan add the pressure
drops of all components upstream of the
drain pan, including the cooling coil, and
add the return duct static pressure. Include
Unit should not be operated without
p-traps. Failure to install a p-traps
may result in overflow of condensate
water.
CAUTION