Lennox LGT Series Unit Information page 54

ELECTRONIC OR ELECTROMECHANICAL THERMOSTAT
1 2 3 4
− 0 1
6
A173
CTRL SMOKE
DETECT
J250 P250 P251 J251
YEL YEL
Y
1 YEL 1
YEL
YEL
Y
2 YEL 2
RED
RED
R
PNK
3 3
BLK BLK
B
GRY
4 4
J252 P252 P253 J253
YEL
Y
1 1
YEL YEL
YEL
Y
2 2
YEL YEL
PNK
R
RED 3 3 RED
GRY
B
BLK 4 4 BLK
15 16 17 1 2
4 3 6 1 2
1
P299
J299
1 2 3 4
A55
MAIN CTRL
1 2 3 4 5 6
J297
P297
R C G Y 1
1 2 3 6
2
B
A
ALL OTHER
THERMOSTAT SIGNALS
REMAIN CONNECTED
AS SHOWN ON THE TOP
TO PROVIDE SUPERMARKET
REHEAT SCHEME USE S86
DEHUMIDISTAT AND K55
SUPERMARKET REHEAT
DENOTES OPTIONAL COMPONENTS
AND WIRING
CLASS 2 FIELD WIRING
Model: LC, LG, LH, LD Series RTU
Thermostat
Voltage: All Voltages
Supersedes: N/A Form No:
FIRE ALARM CONTACT
SUPPLIED BY OTHERS
5
1,5
1 2
DI−1 R
9
2
P387
J387
5 6 7 8 9 10 3
7 8 9 10 1 2 3
J298
P298
3
C Y 1 Y 2
2 6 7
7
TO PROVIDE THREE
COMPRESSOR STAGES.
REQUIRES 3 HEAT,
3 COOL THERMOSTAT
AND K27 RELAY
4
3 STAGE COOLING/
3 STAGE HEATING
538078−01
Rev: 1
Page 54
FROM IAQ
5
WIRING DIAGRAM
8
RED
1 2
8 4 9 10 5 2 7 1 6
4 5 6 7 8 9 10
J298 J297 J299
R C IAQ+
R C IAQ+
1 2 3
1 2 3
7
BACNET GATEWAY
R IAQ+ IAQ−
C
1 3 4 2
7
1 8 7 2
HEATI N G COOLI N G COOLI N G
SECTI O N SECTI O N SECTI O N
A B B3
WI R I N G DI A GRAM F LOW
J387
A55
ACCS ACCS
SECTI O N SECTI O N
C D