Carrier 38YKC Series - Unit Care and Service Preparation; Indoor Coil Maintenance; Outdoor Coil Maintenance; Outdoor Coil Maintenance - Sea Coast

Fig. 8—Typical 24-v Circuit Connections using Carrier Model HP Thermostat with Fan Coils
and No Outdoor Thermostat, 1 Outdoor Thermostat, or 2 Outdoor Thermostats
A97536
24 VAC HOT






R
G
W/W1
Y/Y2
O/W2
R
W3
W2
RVS COOLING








C
B
S1
S2
W2
CARRIER
PROGRAMMABLE
THERMOSTAT
MODEL HP
TWO
OUTDOOR
THERMOSTATS

FA, FB, FC, 
FD, FF, FH
FAN COIL
HEAT 
PUMP


G
Y1/W2
L
R
O
INDOOR FAN


HEAT STAGE 2


COOL/HEAT
STAGE 1
NOT USED
24 VAC COM
NOT USED

TROUBLE
OPTIONAL
OUTDOOR
SENSOR
CONNECTION
Y
C
C
E

ODT


ODT

NOTE: Remove wires from crimp nut in indoor fan coil 
 when installing outdoor thermostats.

IMPORTANT: When using outdoor thermostats, W
2
must be
 energized when requesting supplemental heat.



EHR


EHR

EHR

A97534
24 VAC HOT






R
G
W/W1
Y/Y2
O/W2
R
W2
W3
E
RVS COOLING








C
B
S1
S2
W2
CARRIER
PROGRAMMABLE
THERMOSTAT
MODEL HP
FA, FB, FC,
FD, FF, FH
FAN COIL
HEAT 
PUMP


G
Y1/W2
L
R
O
INDOOR FAN


HEAT STAGE 2


COOL/HEAT
STAGE 1
NOT USED
24 VAC COM
NOT USED

TROUBLE
OPTIONAL
OUTDOOR
SENSOR
CONNECTION
Y
C
C
*
*
*
IF AVAILABLE


*
A98629
24 VAC HOT
R
G
W/W1
Y/Y2
O/W2
RVS COOLING
C
B
S1
S2
CARRIER
PROGRAMMABLE
THERMOSTAT
MODEL HP
40FKA
FK4C
FAN COIL
HEAT
PUMP
Y1/W2
L
INDOOR FAN
HEAT STAGE 2
COOL/HEAT
STAGE 1
NOT USED
24 VAC COM
NOT USED
TROUBLE
OPTIONAL
OUTDOOR
SENSOR
CONNECTION
R
DH
G
W2
O
Y/Y2
C
Y1
W1
W2
R
Y
C
O
J1 JUMPER
J2 JUMPER
A97535
24 VAC HOT






R
G
W/W1
Y/Y2
O/W2
R
W3
W2
E
RVS COOLING








C
B
S1
S2
W2
CARRIER
PROGRAMMABLE
THERMOSTAT
MODEL HP
ONE
OUTDOOR
THERMOSTAT

FA, FB, FC, FD, FF, FH
FAN COIL
HEAT 
PUMP


G
Y1/W2
L
R
O
INDOOR FAN


HEAT STAGE 2


COOL/HEAT
STAGE 1
NOT USED
24 VAC COM
NOT USED

TROUBLE
OPTIONAL
OUTDOOR
SENSOR
CONNECTION
Y
C
C

ODT

NOTE: Remove wires from crimp nut in indoor fan coil 
 when installing outdoor thermostat.

IMPORTANT: When using outdoor thermostat, W
2
must be
 energized when requesting supplemental heat.


5