THX9321 PRESTIGE
®
2.0 AND THX9421 PRESTIGE
®
IAQ WITH EIM
68-0311—02
138
EIM Wiring Diagrams
Typical wiring of a conventional system with up to 3-stage heat and 2-stage cool with one transformer.
Fig. 319. EIM wiring guide — conventional systems.
1 See guides on following pages for thermostat wiring and geothermal radiant heat wiring.
2 Wire a maximum of 4 sensors using the S1-S4 terminals. S1-S4 terminals can be connected to an indoor sensor, outdoor sen-
sor, discharge sensor, return sensor, dry contact device to display an alert or an occupancy sensor for remote setback.
3 Remove jumper(s) if using separate transformers.
4 See “Economizer Module Wiring Diagrams” beginning on page 151.
5 Connect wireless adapter to ABCD for extended wireless range.
HEAT STAGE 1
HEAT STAGE 2
HEAT STAGE 3
FAN
TO THERMOSTAT
STATUS
LEDS
JUMPERS
SENSORS
CONV
FURNACE
R
C
W
W2
W3
G
Y2
Y
TRANSFORMER
120
VAC
24
VAC
COMPRESSOR
STAGE 1
COMPRESSOR
STAGE 2
POWER
HEAT
COOL
FAN
U1
U2
U3
A
CONNECT OPTIONAL
SENSORS TO
S1 AND S2 TERMINALS
S4
S4
S3
S3
CONNECT OPTIONAL
SENSORS TO
S3 AND S4 TERMINALS
A
B
C
D
EIM
2
3
1
4
2
5