7
EIM wiring guide — heat pump systems
Typical wiring of a heat pump system with up to four-stage heat and two-stage
cool with one transformer. (RedLINK FocusPRO up to three-stage heat and two-
stage cool.)
See guides on following pages for thermostat wiring and geothermal radiant
heat wiring.
Wire a maximum of 4 sensors using the S1-S4 terminals. S1-S4 terminals
can be connected to an indoor sensor, outdoor sensor, discharge sensor,
return sensor, dry contact device to display an alert or an occupancy sensor
for remote setback. RedLINK FocusPRO should only use the return sensor to
any of the four sets of S terminals.
L/A terminal sends continuous output when thermostat is set to EM HEAT
mode, except when set up for Economizer or TOD. See Economizer wiring
section. (Only Prestige and RedLINK VisionPRO can be set for Economizer or
TOD.)
CHANGEOVER VALVE
BACKUP HEAT
STAGE 1
FAN RELAY
SENSORS
TO THERMOSTAT
HEAT PUMP
AIR HANDLER
TRANSFORMER
120
VAC
24
VAC
COMPRESSOR
STAGE 1
COMPRESSOR
STAGE 2
O/B
AUX1
AUX2
O/B
BACKUP HEAT
STAGE 2
COMPRESSOR
MONITOR OR
ZONE PANEL
R
C
AUX1
AUX2
G
L/A
Y2
Y
POWER
HEAT
COOL
FAN
U1
U2
U3
STATUS
LEDS
JUMPERS
L/A
EIM
CONNECT OPTIONAL
SENSORS TO
S1 AND S2 TERMINALS
M34250
S4
S4
S3
S3
CONNECT OPTIONAL
SENSORS TO
S3 AND S4 TERMINALS
A
B
C
D
2
2
3
1
3
4
1
2
3
Connect wireless adapter to ABCD for extended wireless range.
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