8
A secondary condensate drain connection has been provided
for areas where the building codes require it. Pitch all drain
lines a minimum of 1/4" per foot to provide free drainage.
Provide required support to the drain line to prevent bowing.
If the secondary drain line is required, run the line separately
from the primary drain and end it where condensate discharge
can be easily seen.
NOTE:
Water coming from secondary line means the coil
primary drain is plugged and needs immediate attention.
Insulate drain lines located inside the building or above a
finished living space to prevent sweating. Install a conden-
sate trap to ensure proper drainage.
NOTE:
When units are installed above ceilings, or in other
locations where damage from condensate overflow may
occur, it is
MANDATORY
to install a field fabricated auxiliary
drain pan under the coil cabinet enclosure.
CAUTION
If 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 12
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
requirements 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 airstream during blower operation.
Field experience has shown condensate drain traps with an
open vertical Tee between the air handler and the conden-
sate drain trap can improve condensate drainage in some
applications, but may cause excessive air discharge out of
the open Tee. The manufacturer does 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 conden-
sate removal from the coil drain pan.
Air Handler
3" MIN.
POSITIVE LIQUID
SEAL REQUIRED
AT TRAP
Drain
Connection
2" MIN.
Figure 12
Use of a condensate removal pump is permitted when nec-
essary. This condensate pump should have provisions for
shutting off the control voltage should a blocked drain occur.
A trap must be installed between the unit and the conden-
sate pump.
IMPORTANT NOTE:
The evaporator coil is fabricated with
oils that may dissolve styrofoam and certain types of plastics.
Therefore, a removal pump or float switch must not contain
any of these materials.
Tip
: Priming the “P” trap may avoid improper draining at the
initial installation and at the beginning of the cooling season.
9
Ductwork
This air handler is designed for a complete supply and return
ductwork system.
To ensure correct system performance, the ductwork is to be
sized to accommodate 350-450 CFM per ton of cooling with
the static pressure not to exceed 0.5" in w.c. Refer to ACCA
Manual D, Manual S and Manual RS for information on duct
sizing and application. Flame retardant ductwork is to be
used and sealed to the unit in a manner that will prevent leak-
age.
NOTE:
A downflow application with electric heat must have
an L-shaped sheet metal supply duct without any outlets or
registers located directly below the heater.
9.1 Return Ductwork
DO NOT LOCATE THE RETURN DUCTWORK IN AN
AREA THAT CAN INTRODUCE TOXIC, OR OBJEC-
TIONABLE FUMES/ODORS INTO THE DUCTWORK.
The return ductwork is to be connected to the air han-
dler bottom (upflow configuration).
Do not operate this product without all the ductwork
attached.
10
Return Air Filters
Each installation must include a return air filter. This filtering
may be performed at the air handler using the factory filter
rails or externally such as a return air filter grille. When using
the factory filter rails, a nominal 16x20x1”, 20x20x1” or
24x20x1” (actual dimension must be less than 23-½”x20”)
filter can be installed on a B, C and D cabinet respectively
(the cabinet size is the seventh letter of the model number).
11
Electric Heat
Refer to the installation manual provided with the electric heat
kit for the correct installation procedure. All electric heat must
be field installed. If installing this option, the ONLY heat kits
that are permitted to be used are the HKS series. Refer to
the air handler unit’s Serial and Rating plate or the HKS speci-
fication sheets to determine the heat kits compatible with a
given air handler. No other accessory heat kit besides the
HKS series may be installed in these air handlers.
