Honeywell T874 Product Data page 170

T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
THEROMSTAT
FALL
H1
H1 ANTICIPATOR
FALL
H2
RESET HEATER
RISE
CO
RISE
C1
ANTICIPATOR
C1
Fig. 162. Schematic and hookup of T874G with Q674J. Used in heat pump applications.
60-2485—8
SUBBASE
1
FAN SWITCH
AUTO
2
ON
3
4
5
6
SYSTEM SWITCH
EM. HT.
8
AUTO
OFF
9
10
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
170
C815A OUTDOOR
THERMISTOR
T
G
O
R
OUTDOOR
THERMOSTAT
X2
AUX. HT. LED
(GREEN)
W
B
EM. HT.
LED (RED)
F
Y
SYSTEM COMPONENTS
FAN RELAY
COOL
CHANGEOVER VALVE
1
L1
(HOT)
L2
AUX. HT. RELAY
EM. HT. RELAY
COMPRESSOR
CONTACTOR
M5725