wiring diagrams
575C/575B
Sizes 072 to 120
with
524A-H
SPLIT-SYSTEM HEAT PUMP UNITS
Cancels: WD 575C.90.1
WD 575B.72.1
6/15/03
DIAGRAM INDEX
UNIT
SIZE
575B
072
575C
090-120
524A-H
090-120
ELECTRICAL
CHARACTERISTICS
(V-Ph-Hz)
208/230-3-60
460-3-60
575-3-60
208/230-3-60
460-3-60
575-3-60
Applies to all
TYPE
LABEL DIAGRAM
NUMBER
Control Schematic and Component Arrangement
Not available
Control Schematic and Component Arrangement
Unit Wiring Diagram
38AK540179
38AK540180
38AK540211
Not Available
FIGURE NO.
1
2
2
3 or 4*
5 or 6*
7 or 8*
9
*Units produced after 3/31/03.
LEGEND (Fig. 1-9)
C
CAP
CB
CCH, CH
CDT
CLO
COMP
CTD
DFC
DFT
DGT
EQUIP
FM
GND
HP, HPS
IFC
IFM
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
Contactor, Compressor
Capacitor
Circuit Breaker
Crankcase Heater
Contactor Dummy Terminal
Compressor Lockout
Compressor
Compressor Time Delay
Defrost Control
Defrost Thermostat
Discharge Gas Thermostat
Equipment
Fan Motor
Ground
High-Pressure Switch
Indoor-Fan Contactor
Indoor-Fan Motor
LAR
LAS
LCS
LLSV
LP, LPS
MMR
NEC
OF, OFM
OFR
PL
PS
RV
RVS
TB
TRAN(S)
T’STAT
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
Low Ambient Relay
Low Ambient Switch
Loss-of-Charge Switch
Liquid Line Solenoid Valve
Low-Pressure Switch
Motormaster® Relay
National Electrical Code
Outdoor-Fan Motor
Outdoor-Fan Relay
Plug
Pressure Switch
Reversing Valve
Reversing Valve Solenoid
Terminal Block
Transformer
Thermostat
NOTES (Fig. 1 and 2)
Field Splice
Marked Wire
Terminal (Marked)
Terminal (Unmarked)
Terminal Block
Splice
Factory Power Wiring
Factory Control Wiring
Field Control Wiring
Field Power Wiring
Accessory or Optional Wiring
To indicate common potential only,
not to represent wiring.
NOTES (Fig. 3-8)
1. Factory wiring is in accordance with National Electrical Code (NEC). Field modifications or additions
must be in compliance with all applicable codes.
1. If any of the original wire furnished must be
replaced, it must be replaced with type 90° C wire or
its equivalent.
2. Use copper conductors only.
3. CAUTION: Not suitable for use on systems exceeding
150 volts to ground.
4. Manual reset circuit breaker is integral to the
transformer.
2. For thermostat and subbase part no. see price pages.
3. Set heat anticipator at .6.
4. Use copper conductors only.
5. Three-phase motors are protected under primary
single phasing conditions.
6. 39 VA available for field-installed accessories. Control
power requirement for heat pump condensing unit is
36 VA (sealed). Supplied control transformer is 75 VA.
NOTES (Fig. 9)
1. Factory wiring is in accordance with National Electrical Code (NEC). Field modifications or additions
must be in compliance with all applicable codes.
2. Use copper conductors only.
SEQUENCE OF OPERATION —
575B OUTDOOR UNIT WITH
524A-H INDOOR UNIT
When power is supplied to unit, the transformer (TRAN) and
crankcase heater (CCH) are energized.
Cooling
On a call for cooling, the thermostat completes the following
circuits: R-G, R-Y, and R-O. If the compressor recycle delay of
3 minutes is complete, the compressor and outdoor fan start.
The reversing valve is energized for cooling and the indoorfan motor starts.
When the thermostat is satisfied, the circuits are opened,
and the compressor, outdoor-fan motor, and indoor-fan motor
stop. The reversing valve is deenergized.
Heating
On a call for heating, the thermostat completes the following
circuits: R-G and R-Y. If the compressor recycle delay of
3 minutes is complete, the compressor and outdoor fan start.
The indoor-fan motor will also start.
If room temperature continues to fall, the thermostat completes circuit R-W. If the optional electric heat package is
used, the heat relay is energized, and the electric heaters are
energized.
When the thermostat is satisfied, the circuits are opened,
and the compressor, outdoor-fan motor, heaters, and indoorfan motor stop.
Defrost
The Defrost board (DB) is a time and temperature control,
which includes a field-selectable time period between checks
for frost (30, 50, and 90 minutes). Electronic timer and
defrost cycle start only when contactor is energized and
defrost thermostat (DFT) is closed (below 36 F [2.2 C]).
Defrost mode is identical to Cooling mode, except outdoor-fan
motor (OFM) stops and a bank of supplemental electric heat
(if equipped) turns on to warm air supplying the conditioned
space. Defrost mode is terminated when the DFT reaches
51 F (10.6 C).
Low Ambient
Cooling head pressure control at low ambient conditions is
accomplished through a low ambient relay and switch. The
switch is factory set to close at 250 psig and open at 100 psig.
In Heating mode, the low ambient switch is bypassed by normally closed contacts on the low ambient relay.
Air Circulation
When the fan switch is at FAN ON, the indoor-air fans operate continuously to provide ventilation. The thermostat operates the other components as described above.
Emergency Heat Cycle
If the compressor is inoperative due to a tripped safety
device, the second stage of the thermostat automatically
energizes the indoor-air fan and the electric resistance heaters (if equipped).
SEQUENCE OF OPERATION —
575C OUTDOOR UNIT WITH
524A-H INDOOR UNIT
When power is supplied to unit, the transformer (TRAN) is
energized. The crankcase heater is also energized.
Cooling
With the thermostat in the cooling position, and when the
space temperature comes within 2° F of the cooling set point,
the thermostat makes circuit R-O. This energizes the reversing valve solenoid (RVS) and places the unit in standby condition for cooling.
As the space temperature continues to rise, the second stage
of the thermostat makes, closing circuit R-Y. When compressor time delay (5 ± 2 minutes) is completed, a circuit is made
to contactor (C), starting the compressor (COMP) and
outdoor-fan motor (OFM). Circuit R-G is made at the same
time, energizing the indoor-fan contactor (IFC) and starting
the indoor-fan motor (IFM) after one-second delay.
When the thermostat is satisfied, contacts open, deenergizing C. The COMP, IFM, and OFM stop.
Heating
On a call for heat, thermostat makes circuits R-Y and R-G.
When compressor time delay (5 ± 2 minutes) is completed, a
circuit is made to C, starting COMP and OFM. Circuit R-G
also energizes IFC and starts IFM after a 1-second delay.
Should room temperature continue to fall, circuit R-W is
made through second-stage thermostat bulb. If optional electric heat package is used, a relay is energized, bringing on
supplemental electric heat. When thermostat is satisfied,
contacts open, deenergizing contactor and relay; motors and
heaters deenergize.
Defrost
Defrost board (DB) is a time and temperature control, which
includes a field-selectable time period between checks for
frost (30, 50, and 90 minutes). Electronic timer and defrost
cycle start only when contactor is energized and defrost thermostat (DFT) is closed (below 28 F [–2.2 C]).
Defrost mode is identical to Cooling mode, except outdoor-fan
motor (OFM) stops and a bank of supplemental electric heat
turns on to warm air supplying the conditioned space.
Defrost mode is terminated when the DFT reaches 65 F
(18.3 C).
—2 —
DANGER: ELECTRICAL SHOCK HAZARD
DISCONNECT POWER BEFORE SERVICING
CONNECTION DIAGRAM
POWER SUPPLY PER
N.E.C. AND LOCAL
CODES 208/230 VAC,
60 HZ, 3 PH.
BL
R
LOW AMBIENT
SWITCH
R
R
L3
L3
T2
L2
L2
T1
L1
COMP
BL
T1
BK
3
BK
1
L2
T2
T2
T3
CCH
COMPRESSOR
ATTACH GROUND
T1
SEC
CAP
LAS
R
BK
FAN
CAP
DEFROST Y-RV
CONTROL
FM
R
PS1
BL
BK
BK
R C
BL (WHEN
USED)
SEN
PS2
LP/HP
PS1
R-RV
W
Y
O
O
BL
R
CC
DEFROST
CONTROL PS2
RV
COIL
C
COIL
LP/HP
LP/HP
TWO SWITCH WIRING
BL
RV
PS1
O Y W
FM
Y-RV
FAN
Y
DF
BK BR R
TRANSFORMER NOTE 4
24V
Y
PS2
DFC
2
USED)
208/230V
BL
BL
CC
BL BR R
1
FAN
LOW AMBIENT
RELAY
(WHEN
BK RV
BK COIL
RV
PL
CONT.
CONTACTOR
L1
BK
G
COIL
L1
T1
CONTACTOR
T3
COIL
TRANS
2
CCH
+t°
L3
BK
PRI
BL
DIAGRAM
208/230 VAC, 60 HZ, 3 PH POWER SUPPLY
RESET
LOW
AMBIENT
RELAY
GROUND EQUIPMENT
PER N.E.C. AND
LOCAL CODES.
T2
T3
BL
T3
LADDER
DEFROST HEAT
COMPRESSOR
HEAT/COOL
DF
RRV
R C
O Y W
LAR
COMMON
24 VAC
Fig. 1 — Control Schematic and Component Arrangement — 575B072 (208/230 V)
—3 —
SEN
DEFROST HEAT
COMPRESSOR
HEAT/COOL
COMMON
24 VAC
DANGER: ELECTRICAL SHOCK HAZARD
DISCONNECT POWER BEFORE SERVICING
CONNECTION DIAGRAM
LADDER
BL
R
LOW AMBIENT
SWITCH
T3
T3
L3
L3
T2
L2
L2
BL
PRI
T1
L1
BK
TRANS
BL
G
1
DEFROST
RELAY
SEC
2
L1
BK
BL
COIL
COMPRESSOR
T3
CCH
2
Y
COIL
T2
T2
ATTACH
GROUND
BK
COIL
T1
CAP
R
CAP
FAN
BL
LAS
Y
FM
DEFROST Y-RV
CONTROL
BK
BK
RV
R
RV
COIL
24V
DFR
RV
PL
PS1
Y
BK
BK
DF
R C
FM
PS2
LP/HP
O Y W
PS1
DEFROST CC
CONTROL PS2
LP/HP
DEFROST HEAT
COMPRESSOR
HEAT/COOL
COMMON
24 VAC
W
Y
O
BL
R
Y-RV
RV
PS1
TWO SWITCH WIRING
O
FAN
SEN
R-RV
BL
1
3
TRANSFORMER NOTE 4
Y
PS2
BK BR R
2
575/460V
BL
BL
CC
BL BR R
1
LOW AMBIENT DEFROST
RELAY
RELAY
RESET
1
CONT.
CONTACTOR
T3
BK
3
L1
T1
L2
CONTACTOR
T1
BK
3
CCH
+t°
L3
T2
COMP
BL
LOW
AMBIENT
RELAY
575/460 VAC
60 HZ 3PH
R
R
DIAGRAM
575/460 VAC 60 HZ 3PH
DF
RRV
R C
C
COIL
LP/HP
SEN
O Y W
LAR
Fig. 2 — Control Schematic and Component Arrangement — 575B072 (460 and 575 V)
—4 —
COIL
DEFROST HEAT
COMPRESSOR
HEAT/COOL
COMMON
24 VAC
Fig. 3 — Control Schematic and Component Arrangement — 575C090-120 (208/230 V) Units Produced Before 3/31/03
—5 —
Fig. 4 — Control Schematic and Component Arrangement — 575C090-120 (208/230 V) Units Produced After 3/31/03
—6 —
Fig. 5 — Control Schematic and Component Arrangement — 575C090-120 (460 V) Units Produced Before 3/31/03
—7 —
Fig. 6 — Control Schematic and Component Arrangement — 575C090-120 (460 V) Units Produced After 3/31/03
—8 —
Fig. 7 — Control Schematic and Component Arrangement — 575C090-120 (575 V) Units Produced Before 3/31/03
—9 —
Fig. 8 — Control Schematic and Component Arrangement — 575C090-120 (575 V) Units Produced After 3/31/03
—10—
CIRCUIT BREAKER
C5HP AND LARGER
524A-H
524A-H
Fig. 9 — 524A-H Wiring Detail
—11—
Copyright 2003 Bryant Heating & Cooling Systems
CATALOG NO. 5357-505