Honeywell T874 Product Data page 148

T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
THERMOSTAT
H1
C1
FALL
H1/C1
ANTICIPATOR
H2
FALL
H2 ANTICIPATOR
RESET
1
POWER SUPPLY. PROVIDE DISCONNECT
MEANS AND OVERLOAD PROTECTION
AS REQUIRED.
FACTORY-INSTALLED JUMPER.
2
Fig. 130. Schematic and hookup of T874R with Q674L. Used in heat pump applications.
60-2485—8
SUBBASE
2
FAN
SWITCH
AUTO
ON
3
4
SYSTEM
5
SWITCH
EM. HT.
HEAT
6
OFF
COOL
11
12
148
SYSTEM COMPONENTS
O
COOL
CHANGEOVER VALVE
G
R
W1
AUX. HT.
2
LED
EM. HT. RELAY
(YELLOW)
E
CHECK
X
LED
(RED)
C
C815A OUTDOOR
THERMISTOR
SYSTEM
LED (GREEN)
T
Y
FAN RELAY
L1
(HOT)
L2
1
COMPRESSOR
FAILURE
COMPRESSOR
CONTACTOR
M1628A