AAON H3 Series, Установка, эксплуатация и обслуживание

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For condensate drain lines, the line must be
the same pipe size or larger than the drain
connection, include a p-trap, and pitch
downward toward drain. Use an air break
with long runs of condensate lines. See
Installation section of this manual for more
information.
Condensate Drain Piping
A p-trap and drain line must be installed on
the drain connection, with the p-trap not to
exceed 15.25 cm (6”) from the drain
connection. The lines must be the same pipe
size or larger than the drain connection,
include a p-trap, and pitch downward toward
drain. Use an air break 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 must
conform to all applicable governing codes.
Figure 17 - Drain Trap
Note:
The drain pan connection is a 24.4mm
(1”) MPT fitting.
The X dimension on the draw-through trap
must be at least equal to the absolute value of
the negative static pressure in the drain pan
plus 2.54 centimeters (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 the
dirt allowance pressure drop for the filters to
account for the worst-case scenario.
The height from top of the bottom bend of the
trap to the bottom of the leaving pipe must be
at least equal to one half of the X dimension.
This ensures that enough water is stored in
the trap to prevent losing the drain seal during
unit startup
Note: The absolute value of the fan inlet
pressure will always be greater than or equal
to the absolute value of the static pressure in
the drain pan on draw-through units, so the
fan inlet pressure is a safe value to use for the
drain pan static pressure.
Do not operate unit without a p-trap.
Failure to install a p-trap may result in
overflow of condensate water.
CAUTION
Use an emergency drain pan for all
applications where a risk of water
damage to surrounding structure or
furnishings. Refer to local codes.
CAUTION