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575J unit control system requires a conventional electric ther-
mostat that will energize the G terminal on a call for Cool and
Heat mode. Do not configure the thermostat a heat pump type;
Heat mode will not work with a thermostat configured for heat
pump.
Locate the thermostat accessory on a solid wall in the condi-
tioned space to sense average temperature in accordance with
the thermostat installation instructions.
If the thermostat contains a logic circuit requiring 24-v power,
use a thermostat cable or equivalent single leads of different
colors with minimum of five leads between the 575J unit's out-
door unit connection board and the indoor unit connection
board. If the thermostat does not require a 24-v source (no "C"
connection required), use a thermostat cable or equivalent with
minimum of four leads. One additional lead is required be-
tween the indoor unit connection board and the thermostat for
terminal G. If the accessory electric heat is used, one additional
wire is required between the indoor unit connection board and
the thermostat for terminal W2. Check the thermostat installa-
tion instructions for additional features which might require
additional conductors in the cable.
NOTE: Two-stage units require an additional wire for the Y2
connection.
For wire runs up to 50 ft (15 m), use no. 18 AWG (American
Wire Gauge) insulated wire (35°C minimum). For 50 to 75 ft
(15 to 23 m), use no. 16 AWG insulated wire (35°C minimum).
For over 75 ft (23 m), use no. 14 AWG insulated wire (35°C
minimum). All wire sizes larger than no. 18 AWG cannot be
directly connected to the thermostat and will require a junction
box and splice at the thermostat.
THERMOSTAT
R
G
Y1
O/B/Y2
W1
W2
C
Fig. 13 — Typical Remote Thermostat Connections
EXTERNAL CONTROL DEVICES
The 575J control transformers provide 24-v NEC Class 2 pow-
er sources to energize external control devices. These devices
will include the indoor fan motor contactor (or control relay or
unit control board in the fan coil unit). These devices may also
include a liquid line solenoid valve, economizer control relay,
supplemental electric heater contactors or control relays and
other devices selected by system designer.
Control transformer TRAN1 provides control power through
terminal R to C on the 575J's outdoor unit field connection ter-
minal strip for supply fan motor interlock. This source may
also be used to energize economizer control relay and electric
heater contactors or relays. Maximum available power is 50 va.
Check concurrent loadings by external control devices. If the
maximum concurrent loading exceeds 50 va, purchase and in-
stall the accessory Transformer-Relay package (available for
208/230 and 460-v units).
Control transformer TRAN2 provides control power through
terminal A1 (9) to C for the liquid line solenoid. Maximum
available power is 15 va. This output is switched ON/OFF by
the Solenoid Valve Relay (field-supplied, use Bryant Service
Part P/N HN61PC005).
15
REFER
TO FAN
COIL
LABEL
IN
CONTROL
BOX
LLSV
HEAT PUMP INDOOR UNIT
ELECTRIC HEATER
TB2
W1
H1
W2
H2
C
HEAT PUMP INDOOR UNIT
WITH ELECTRIC HEATER
OUTDOOR UNIT
CONNECTION
BOARD (TB)
1
R
2
Y1
3
Y2
4
W1
5
W2
6
G
7
C
8
X
9
A1
10
A2
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