Instructions / Assembly

14
12.4 Electrical Connections – Supply Voltage
FIRE HAZARD!
To avoid the risk of property damage, personal injury
or fire, use only copper conductors.
IMPORTANT NOTE: USE COPPER CONDUCTORS ONLY.
Knockouts are provided on the air handler top panel and
sides of the cabinet to allow for the entry of the supply
voltage conductors, as shown in Figure 13. If the knockouts
on the cabinet sides are used for electrical conduit, an
adapter ring must be used in order to meet UL1995 safety
requirements. An NEC or CEC approved strain relief is to be
used at this entry point. Some codes/municipalities require
the supply wire to be enclosed in conduit. Consult your
local codes.
Side of
Cabinet
Top of
Cabinet
KNOCK-OUT FOR ELECTRICAL CONNECTIONS
Figure 13
12.4.1 Air Handler Only (Non-Heat Kit Models)
The building supply connects to the stripped black
and red wires contained in the air handler electrical
compartment cavity. A ground screw is also contained
in this area. Attach the Supply wires to the air han-
dler conductors as shown in the unit wiring diagram
using appropriately sized solderless connectors or
other NEC or CEC approved means.
12.4.2 Air Handler - Non-Circuit Breaker Heat
Kits
A terminal block is provided with the HKS kit to at-
tach the power supply and air handler connections.
Follow the HKS Installation Manual and wiring diagram
for complete wiring details.
12.4.3 Air Handler With Circuit Breaker Heat Kit
The air handler has a plastic cover on the upper ac-
cess panel that will require either one or both sec-
tions to be removed to allow the heat kit circuit
breaker(s) to be installed. The circuit breakers have
lugs for power supply connection. See the HKS Instal-
lation Instructions for further details.
12.5 Low Voltage Connections
Several combinations of low voltage schemes are pos-
sible, depending on the presence of a heat kit and
whether the heat kit is single-stage or multi-stage,
whether the outdoor section is an air conditioner or
heat pump, and whether the outdoor section is single-
stage or two-stage. The 24V-control voltage connects
the air handler to the room thermostat and condenser.
Low voltage wiring must be copper conductors. A mini-
mum of 18AWG must be used for installations up to
100 feet. Low voltage wiring must be connected
through the top of the cabinet or either side. See the
“Thermostat Wiring” section of this manual for typi-
cal low voltage wiring connections.
12.5.1 Thermostats
Second-stage heat can be accomplished by a multi-
stage heating thermostat or the addition of an out-
door thermostat as shown in wiring schematics on page
19. Follow the thermostat manufacturer’s instruc-
tions for installation.
12.6 Speed Tap Adjustment
ARUF**14** air handlers have multi-speed PSC motors.
The color of the wire coming from the motor to the
“COM” terminal on the control board defines at which
speed the motor will operate. Black wire is high speed,
blue wire is medium speed and red wire is low speed.
To change speeds, remove the wire attached to the
“COM” terminal on the control board, and swap it
with the wire (on terminal “M1” or “M2”) with the
color that will give the desired speed.
ASPT**14** air handlers feature energy efficient blower
motors. The motors run at a constant torque with very
low power consumption and are energized by 24 VAC.
Adjust the CFM by changing the 24 VAC leads to the
desired speed tap on the terminal block. The ASPT
blower motor speeds are programmed to deliver ad-
equate airflow at rated external static pressure and
with 60 second off time delay. For details, refer to
the specification sheet applicable to your model.
NOTE: In some models, not all speed taps are allowable for
certain electric heat applications. Refer to Table 5 for
minimum speed.