Honeywell THX9421 Thermostat User Manual


 
THX9321 PRESTIGE
®
2.0 AND THX9421 PRESTIGE
®
IAQ 2.0 WITH EIM
68-0311—01 104
EIM Wiring Diagrams
Typical wiring of a conventional system with up to 3-stage heat and 2-stage cool with one transformer.
Fig. 208. EIM wiring guide — conventional systems.
1 See guides on following pages for thermostat wiring and geothermal radiant heat wiring.
2 Wire a maximum of 2 sensors using the S1 and S2 terminals. See ISU 5000-6190 for options.
3 Remove jumper(s) if using separate transformers.
4 See “Economizer Module Wiring Diagrams” beginning on page 116.
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
(MAX. 2 SENSORS)
EIM
1
3
2
4
M32945A