14
12.4 Electrical Connections – Supply Voltage
CAUTION
FIRE HAZARD!
TO AVOID THE RISK OF PROPERTY DAMAGE, PERSONAL INJU-
RY OR FIRE, USE ONLY COPPER CONDUCTORS.
IMPORTANT NOTE: USE COPPER CONDUCTORS ONLY
FROM DISCONNECT OR ELECTRICAL PANEL TO THE
AIR HANDLER.
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 en-
try 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 com-
partment cavity. A ground screw is also contained in this
area. Attach the Supply wires to the air handler conduc-
tors as shown in the unit wiring diagram using appropri-
ately 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 attach
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 soft plastic cover on the upper ac-
cess panel and can be removed to allow the heater kit
circuit breaker to be installed. The circuit breakers have
lugs for power supply connection. See the HKS Installa-
tion Instructions for further details.
12.5 Low Voltage Connections
Several combinations of low voltage schemes are possi-
ble, depending on the presence of a heat kit and wheth-
er 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 minimum of 18AWG must
be used for installations up to 100 feet. Low voltage wir-
ing must be connected through the top of the cabinet or
either side. See the “Thermostat Wiring” section of this
manual for typical 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 outdoor
thermostat as shown in wiring schematics on page 19.
Follow the thermostat manufacturer’s instructions for in-
stallation.
12.6 Speed Tap Adjustment
ARUF**14** air handlers have multi-speed PSC mo-
tors. 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.
