Honeywell T874 Product Data page 133

THERMOSTAT
FALL
C1
H1
H1/C1
ANTICIPATOR
H2
ANTICIPATOR
H2 FALL
1
POWER SUPPLY. PROVIDE DISCONNECT
MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
Fig. 112. Schematic and hookup of T874R with Q674L. Used in heat pump applications.
SUBBASE
2
FAN
SWITCH
AUTO
ON
3
4
SYSTEM
SWITCH
5
EM. HT.
6
HEAT
OFF
COOL
133
T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
O
G
R
COMPRESSOR
FAILURE
L1
EM. HT. LED
(RED)
X
AUX. HT. LED
(GREEN)
W2
Y
E
SYSTEM COMPONENTS
COOL CHANGEOVER
VALVE
FAN RELAY
L1
(HOT)
L2
1
AUX. HT. RELAY
COMPRESSOR
CONTACTOR
EM. HT. RELAY
M8383
60-2485—8