Warning, Caution – Bryant 574D User Manual
Page 11

11
Step 10 — Install Electrical Connections
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death.
The unit cabinet must have an uninterrupted, unbroken
electrical ground. This ground may consist of an electrical
wire connected to the unit ground screw in the control
compartment, or conduit approved for electrical ground
when installed in accordance with NEC, ANSI/NFPA
American National Standards Institute/National Fire
Protection Association (latest edition) (in Canada, Canadian
Electrical Code CSA C22.1) and local electrical codes.
!
WARNING
UNIT COMPONENT DAMAGE HAZARD
Failure to follow this caution may result in damage to the
unit being installed.
1. Make all electrical connections in accordance with NEC
ANSI/NFPA (latest edition) and local electrical codes
governing such wiring. In Canada, all electrical
connections must be in accordance with CSA standard
C22.1 Canadian Electrical Code Part 1 and applicable
local codes. Refer to unit wiring diagram.
2. Use only copper conductor for connections between
field--supplied electrical disconnect switch and unit. DO
NOT USE ALUMINUM WIRE.
3. Be sure that high--voltage power to unit is within
operating voltage range indicated on unit rating plate. On
3--phase units, ensure phases are balanced within 2
percent. Consult local power company for correction of
improper voltage and/or phase imbalance.
4. Insulate low--voltage wires for highest voltage contained
within conduit when low--voltage control wires are in
same conduit as high--voltage wires.
5. Do not damage internal components when drilling
through any panel to mount electrical hardware, conduit,
etc.
!
CAUTION
HIGH--VOLTAGE CONNECTIONS
When routing power leads into unit, use only copper wire between
disconnect and unit. The high voltage leads should be in a conduit
until they enter the duct panel; conduit termination at the duct
panel must be watertight.
The unit must have a separate electrical service with a
field--supplied, waterproof disconnect switch mounted at, or within
sight from, the unit. Refer to the unit rating plate, NEC and local
codes for maximum fuse/circuit breaker size and minimum circuit
amps (ampacity) for wire sizing.
The field--supplied disconnect switch box may be mounted on the
unit over the high--voltage inlet hole when the standard power and
low--voltage entry points are used (See Fig. 3 and 4 for acceptable
location).
See unit wiring label and Fig. 11 for reference when making high
voltage connections. Proceed as follows to complete the
high--voltage connections to the unit.
Single phase units:
1. Run the high--voltage (L1, L2) and ground lead into the
control box.
2. Connect ground lead to chassis ground connection.
3. Locate the black and yellow wires connected to the line side
of the contactor.
4. Connect field L1 to black wire on connection 11 of the
compressor contactor.
5. Connect field wire L2 to yellow wire on connection 23 of
the compressor contactor.
Three--phase units:
1. Run the high--voltage (L1, L2, L3) and ground lead into the
control box.
2. Connect ground lead to chassis ground connection.
3. Locate the black and yellow wires connected to the line side
of the contactor.
4. Connect field L1 to black wire on connection 11 of the
compressor contactor.
5. Connect field wire L2 to yellow wire on connection 13 of
the compressor contactor.
6. Connect field wire L3 to blue wire from compressor.
SPECIAL PROCEDURES FOR 208--V OPERATION
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death.
Make sure the power supply to the unit is switched OFF
before making any wiring changes. With disconnect switch
open, move black wire from transformer (3/16 in.) terminal
marked 230 to terminal marked 208. This retaps transformer
to primary voltage of 208 vac.
!
WARNING
ELECTRICAL SHOCK FIRE/EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury or death and property damage.
Before making any wiring changes, make sure the gas
supply is switched off first. Then switch off the power
supply to the unit and install lockout tag.
!
WARNING
CONTROL VOLTAGE CONNECTIONS
Do not use any type of power--stealing thermostat. Unit control
problems may result.
Use no. 18 American Wire Gage (AWG) color--coded, insulated
(35_C minimum) wires to make the control voltage connections
between the thermostat and the unit. If the thermostat is located
more than 100 ft (30.5 m) from the unit (as measured along the
control voltage wires), use no. 16 AWG color--coded, insulated
(35_C minimum) wires.
STANDARD CONNECTION
Remove knockout hole located in the flue panel adjacent to the
control access panel (See Fig. 3 and 4). Remove the rubber
grommet from the installer’s packet (included with unit) and install
grommet in the knockout opening. Provide a drip loop before
running wire through panel.
574D