Honeywell T874 Product Data page 162

T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
THERMOSTAT
H1
ANTICIPATOR
FALL
H1
H2
ANTICIPATOR
FALL
H2
CO
RISE
C1
ANTICIPATOR
C1
RISE
Fig. 151. Schematic and hookup of T874G with Q674F. Used in heat pump applications.
60-2485—8
SUBBASE
1
FAN
SWITCH
2
AUTO
ON
4
6
SYSTEM
SWITCH
OFF
EM. HT.
HEAT
AUTO
8
COOL
9
10
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
1
PROTECTION AS REQUIRED.
2
OPTIONAL FIELD WIRE JUMPER TO CYCLE W2 WITH H1 IN EM. HT.
(FASTER RESPONSE).
R
W2
EM. HT.
LED
(RED)
E
2
X
H
Y
G
O
162
SYSTEM COMPONENTS
EM. HT. RELAY
L2
CONTACT 1
L1
(HOT)
1
T6031 REFRIGERATON/
TEMPERATURE
CONTROLLER
EM. HT. RELAY
R8233B
COMPRESSOR
CONTACTOR
Y R
COM
G
EM.
HT.
W
SEQUENTIAL
RELAY
O
FAN
C DF RS
1
L1 REVERSING
L2
(HOT) SOLENOID
EM. HT.
FAN
M4710