Page 12
STEP 5 -- ELECTRICAL -- Circuit Sizing and Wire Routing
In the U.S.A., wiring must conform with current local codes and the cur
rent National Electric Code (NEC). In Canada, wiring must conform with
current local codes and the current Canadian Electrical Code (CEC).
Refer to the furnace or air handler installation instructions for addition
al wiring application diagrams and refer to unit nameplate for minimum
circuit ampacity and maximum overcurrent protection size.
24VAC TRANSFORMER
Use the transformer provided with the furnace or air handler for
low‐voltage control power (24VAC - 40 VA minimum).
WARNING
Electric Shock Hazard. Can cause injury or
death. Unit must be grounded in
accordance with national and local codes.
Line voltage is present at all components
when unit is not in operation on units with
single‐pole contactors. Disconnect all
remote electric power supplies before
opening access panel. Unit may have
multiple power supplies.
IMPORTANT !
If unit is equipped with a crankcase heater, it should be
energized 24 hours before unit start-up to prevent com
pressor damage as a result of slugging.
CAUTION
ELECTROSTATIC
DISCHARGE
(ESD)
Precautions and
Procedures
Electrostatic discharge can affect
electronic components. Take care during
unit installation and service to protect the
unit's electronic controls. Precautions
will help to avoid control exposure to
electrostatic discharge by putting the
unit, the control and the technician at the
same electrostatic potential. Touch hand
and all tools on an unpainted unit surface
before performing any service procedure
to neutralize electrostatic charge.
Refer to the unit nameplate for minimum circuit ampacity, and
maximum fuse or circuit breaker (HACR per NEC). Install power wiring
and properly sized disconnect switch.
NOTE -
Units are approved for use only with copper conductors.
Ground unit at disconnect switch or connect to an earth ground.
SIZE CIRCUIT AND INSTALL DISCONNECT SWITCH
1
NOTE -
24VAC, Class II circuit connections are made in the control
panel.
Install room thermostat (ordered separately) on an inside wall
approximately in the center of the conditioned area and 5 feet (1.5m)
from the floor. It should not be installed on an outside wall or where it
can be affected by sunlight or drafts.
THERMOSTAT
5 FEET
(1.5M)
INSTALL THERMOSTAT
2
DISCONNECT
SWITCH
MAIN FUSE BOX/
BREAKER PANEL
FIGURE 12
