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5
Make Electrical Connections
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or
death.
Do not supply power to unit with compressor terminal box
cover removed.
NOTE
: Use copper wire only between disconnect switch and unit.
NOTE
: Install branch circuit disconnect of adequate size per NEC
to handle unit starting current. Locate disconnect within sight from
and readily accessible from unit, per Section 440–14 of NEC.
Route Ground and Power Wires
Remove access panel to gain access to unit wiring. Extend wires
from disconnect through power wiring hole provided and into unit
control box.
Connect Ground and Power Wires
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or
death.
The unit cabinet must have an uninterrupted or unbroken
ground to minimize personal injury if an electrical fault should
occur. The ground may consist of electrical wire or metal
conduit when installed in accordance with existing electrical
codes.
Connect ground wire to ground connection in control box for
safety. Connect power wiring to contactor as shown in Fig. 8.
DISCONNECT
PER N.E.C. AND/OR
LOCAL CODES
CONTACTOR
GROUND
LUG
FIELD GROUND
WIRING
FIELD POWER
WIRING
BLUE
3 PHASE ONLY
A94025
Fig. 8 -- Line Connections
A00010
Fig. 9 -- 3–Phase Monitor Control
(Applies to 3–Phase Units Only)
Table 3 – 3–Phase Monitor LED Indicators
LED
STATUS
OFF
No call for compressor operation
FLASHING
Reversed phase
ON
Normal
Connect Control Wiring
Route 24v control wires through control wiring grommet and
connect leads to control wiring. See Thermostat Installation
Instructions for wiring specific unit combinations. (See Fig. 10.)
Use No. 18 AWG color–coded, insulated (35
°
C minimum) wire. If
thermostat is located more than 100 ft (30.5 m) from unit, as
measured along the control voltage wires, use No. 16 AWG
color–coded wire to avoid excessive voltage drop.
All wiring must be NEC Class 1 and must be separated from
incoming power leads.
Use furnace transformer, fan coil transformer, or accessory
transformer for control power, 24v/40va minimum.
NOTE
:
Use of available 24v accessories may exceed the
minimum 40va power requirement. Determine total transformer
loading and increase the transformer capacity or split the load with
an accessory transformer as required.
24 VAC HOT
R
C
W2
Y
G
R
C
RVS COOLING
C
W2
HP THERMOSTAT
TYPICAL
FAN COIL
HEAT
PUMP
G
O
E
W2
E
W3
R
Y
24 VAC COM
HEAT STAGE 2
COOL/HEAT
STAGE 1
INDOOR FAN
EMERGENCY
HEAT
O
*
*
*
IF AVAILABLE
*
LEGEND
24-V FACTORY WIRING
24-V FIELD WIRING
FIELD SPLICE CONNECTION
OUTDOOR THERMOSTAT
EMERGENCY HEAT RELAY
SUPPLEMENTAL HEAT RELAY
SHR
EHR
ODT
A02325 / A97413
Fig. 10 -- Generic Wiring Diagrams
(See thermostat Installation Instructions
for specific unit combinations)
25H
B
B
/25H
B
C
/25H
C
D