Honeywell CHRONOTHERM T8621A User Manual page 13

Fig. 12—T8621C,D single stage heat pump with heating changeover. HEAT-AUTO-COOL-OFF system and
AUTO-ON fan switching.
THERMOSTAT
LOGIC CIRCUIT
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
1
PROTECTION AS REQUIRED.
APPLICABLE ONLY ON T8621 MODEL WITH REMOTE SENSOR.
2
RECOMMENDED INTERCONNECT CABLE: 18-GAUGE THERMOSTAT
3
CABLE, 200 ft. [61 m] MAXIMUM LENGTH. ROUTE INTERCONNECT
CABLE AWAY FROM SOURCES OF ELECTRICAL NOISE.
5
POWER
SUPPLY
HEAT
AUTO
COOL
OFF
SUBBASE
LOGIC/
CONTROL
CIRCUIT
13
HIGH
LIMIT
HIGH
LIMIT
H1
SYSTEM
SWITCH
H2
C2
C1
FAN
SWITCH
AUTO
ON
4 T8621D ONLY.
DENOTES THERMOSTAT TO SUBBASE CONNECTIONS.
5
NOTE: SET CYCLE RATE TO HOT WATER SETTING (3 cph).
THERMOSTAT DOES NOT PROVIDE MINIMUM OFF TIME IN
HEATING.
T8621A,C,D
INSTALLATION
L1
(HOT)
L2
1
SYSTEM
TRANSFORMER
R
C
HEATING
CHANGEOVER
W1
COMPRESSOR
CONTACTOR
W2
4
Y2
Y1
FAN RELAY
G
RC
2
S1 S1
S2 S2
S3 S3
3
202905 REMOTE
SENSOR
M1547C
68-0058—1