3
Filters
Filters are not provided with unit, and must be supplied and in-
stalled in the return air system by the installer. A field installed
filter grille is recommended for easy and convenient access to the
filters for periodic inspection and cleaning. Filters must have
adequate face area for the rated air quantity of the unit. The mini-
mum filter size is 20" x 20" x 1".
Condensate Drain Piping
The coil drain pan has a primary and a secondary drain with 3/4"
NPT female connections. The connectors required are 3/4" NPT
male, either PVC or metal pipe, and should be hand tightened to
a torque of approximately 37 in-lbs. to prevent damage to the
drain pan connection. An insertion depth between .143 to .355
inches (2-5 turns) should be expected at this torque. Use the fe-
male (3/4 NPT) threaded fitting that protrudes outside of the
enclosure for external connections.
1. Ensure drain pan hole is NOT obstructed.
2. To prevent potential sweating and dripping on to finished
space, it may be necessary to insulate the condensate drain
line located inside the building. Use Armaflex® or similar
material.
A Secondary Condensate Drain Connection has been provided for
areas where the building codes require it. Pitch the drain line 1/
4" per foot to provide free drainage. Insulate drain lines located
inside the building to prevent sweating. Install a condensate trap
to ensure proper drainage. If the secondary drain line is required,
run the line separately from the primary drain and end it where it
can be easily seen.
NOTE:
Water coming from this line means the coil primary drain
is plugged and needs clearing.
CAUTION
I
F
SECONDARY
DRAIN
IS
NOT
INSTALLED
,
THE
SECONDARY
ACCESS
MUST
BE
PLUGGED
.
The installation must include a “P” style trap that is located as
close as is practical to the evaporator coil. See
Figure 1
for details
of a typical condensate line “P” trap.
NOTE:
Trapped lines are required by many local codes. In the
absence of any prevailing local codes, please refer to the require-
ments listed in the Uniform Mechanical Building Code.
A drain trap in a
draw-through
application prevents air from
being drawn back through the drain line during fan operation
thus preventing condensate from draining, and if connected to a
sewer line to prevent sewer gases from being drawn into the air-
stream during blower operation. In a
blow-through
application
the drain trap prevents conditioned air from escaping. It is per-
missible in this application to use a shallow trap design some-
times referred to as a running trap.
Unit
3" MIN.
POSITIVE LIQUID SEAL
REQUIRED AT TRAP
Drain
Connection
2" MIN.
Figure 1
The depth of a running trap (Figure 2) should be either 1" or a
depth that permits unrestricted condensate drainage without
excessive air discharge.
Field experience has shown condensate drain traps with an open
vertical Tee between the air handler and the condensate drain
trap can improve condensate drainage in some applications, but
may cause excessive air discharge out of the open Tee. We do not
prohibit this type of drain but we also do not recommend it due to
the resulting air leakage. Regardless of the condensate drain design
used, it is the installer’s responsibility to ensure the condensate
drain system is of sufficient design to ensure proper condensate
removal from the coil drain pan.
Figure 2
When coils are installed above ceilings, or in other locations
where damage from condensate overflow may occur, it is
MAN-
DATORY
to install a field fabricated auxiliary drain pan under the
coil cabinet enclosure. Drain lines from the auxiliary pan must be
installed and terminated so that the homeowner can see water
discharges. A primary condensate drain connection is located in
the drain pan on the bottom of the coil / enclosure assembly. The
female (3/4 fpt) threaded fitting that protrudes outside of the en-
closure is used for external connections.
NOTE:
Wire size based on 60°C rated wire insulation and 30°C
Ambient Temp. (86°F).
For branch circuit wiring (main power supply to unit disconnect),
determine the minimum wire size for the length of run from Table
1 using the circuit ampacity found on the unit rating plate. From
the unit disconnect to unit, the smallest wire size allowable in
Table 1 may be used,
as long as the disconnect is in sight of the
unit
.
