11
HIGH VOLTAGE!
To avoid property damage, personal injury or death
due to electrical shock, this unit MUST have an
electrical ground. The
electrical ground circuit may consist of an
appropriately sized electrical wire connecting the
ground lug in the unit control box to the building
electrical service panel.
Other methods of grounding are permitted if performed
in accordance with the National Electric Code
(NEC)/American National Standards Institute
(ANSI)/National Fire Protection Association (NFPA) 70
and local/state codes. In Canada, electrical grounding
is to be in accordance with the Canadian Electric Code
(CSA) C22.1.
uninterrupted, unbroken
•
Wire used must carry the Minimum Circuit Ampac-
ity (MCA) listed on the unit’s Series and Rating
Plate.
•
Refer to the NEC (USA) or CSA (Canada) for wire siz-
ing. The unit MCA for the air handler and the optional
electric heat kit can be found on the unit Series and
Rating Plate.
•
Wire must be sized to allow no more than a 2% volt-
age drop from the building breaker/fuse panel to
the unit.
•
Wires with different insulation temperature rating have
varying ampacities - be sure to check the temperature
rating used.
Refer to the latest edition of the National Electric Code
or in Canada the Canadian Electric Code when deter-
mining the correct wire size.
13.3 Maximum Overcurrent Protection (MOP)
Every installation must include an NEC (USA) or CEC
(Canada) approved overcurrent protection device.
Also, check with local or state codes for any special
regional requirements.
Protection can be in the form of fusing or HACR style
circuit breakers. The Series and Rating Plate provides
the maximum overcurrent device permissible.
NOTE: Fuses or circuit breakers are to be sized larger
than the equipment MCA but not to exceed the MOP.
13.4 Electrical Connections – Supply Voltage
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 electri-
cal 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
13.4.1 Air Handler Only (Non-Heat Kit Models)
The power supply connects to the stripped black and
red wires contained in the air handler electrical com-
partment. Attach the supply wires to the air handler
conductors as shown in the unit wiring diagram using
appropriately sized solderless connectors or other NEC
or CEC approved means. A ground lug is also pro-
vided in the electrical compartment. The ground wire
from the power supply must be connected to this ground
lug.
13.4.2 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.
13.4.3 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 sections
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 Installation Instruc-
tions for further details.
13.5 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 minimum
of 18AWG must be used for installations up to 50’ and
16AWG for installations over 50’. Low voltage wiring
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.
