16
Split Compact Dedicated Outdoor
Air System Installation Manual
Due to our policy of continuous product innovation, some specifications may change without notification.
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INSTALLATION
Figure 6: Example of a Common Drainage System.
Common Drainage System
It is usual work practice to connect individual Split
Compact DOAS drain pipes to one common drainage
system.
The diameter of the common vertical drain pipe
must be as large as necessary.
The diameter of the
horizontal pipe must be the same or larger than the
vertical drain pipe. To avoid property damage in the
event of the primary drain becoming clogged, and to
optimize drain system performance, it may be prudent
to install a secondary drain line.
Design the drain system to plan for winter opera-
tion (condensate line may freeze up if condensate
does not properly drain away). Drain all generated
condensate from the external condensate pan to an
appropriate area. Install a trap in the condensate lines
as near to the indoor unit coil as possible. To prevent
overflow, the outlet of each trap must be positioned
below its connection to the condensate pan. All traps
must be primed, insulated, and leak tested.
• It is recommended that a dedicated drain pipe be installed for the air conditioning
system. If the drainage system is shared with a rainwater drain, waste water, or
any other type of building drain system, back flow, leaks, ice may form, or noxious
odors may infiltrate the air conditioning system.
• Install a trap if the drain access to the outside faces an undesirable location (i.e.,
sewer), otherwise, noxious odors may infiltrate the air conditioning system.
Common horizontal drain pipe
1/50 to 1/100 Slope
27-1/2 in.
(Maximum pump
lift distance
[depends on indoor
unit type]).
Include trap
at the end.
45° to 60° Angle
Position the vent
down to prevent
debris from entering
the system
45° to 60° Angle
45° to 60° Angle
45° to 60° angle for protection against overflow
Common
vertical
drain pipe
Common Drainage System
