Honeywell T874 Product Data page 186

T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
FALL
RISE
Fig. 185. Schematic and hookup of T874D with Q674E. Used in standard applications.
1 POWER SUPPLY. PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
Fig. 186. Schematic and hookup of T874D with Q674G. Used in standard applications.
60-2485—8
THERMOSTAT
H1
ANTICIPATOR
1
AUTO
FAN
H1
SWITCH
4
H2
ANTICIPATOR
FALL
6
H2
RISE
8
C1
9
C1
ANTICIPATOR
10
C2
ANTICIPATOR
11
C2
1 POWER SUPPLY. PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
THERMOSTAT
FALL
H1
1
H1
ANTICIPATOR
4
5
H2
ANTICIPATOR
FALL
6
H2
7
8
RISE
C1
9
C1
ANTICIPATOR
10
11
RISE
C2
ANTICIPATOR
C2
12
SUBBASE
ON
SYSTEM
SWITCH
OFF
HEAT
AUTO
COOL
SUBBASE
W1
NO
FAN
RH
SWITCH
W2
SYSTEM
SWITCH
B
OFF
AUTO
O
RC
Y2
Y1
186
SYSTEM COMPONENTS
L1
(HOT)
1
HEAT RELAY
W1
G
FAN RELAY
RC
W2
HEAT RELAY 2
RH
IGNITION
RELAY
B
COMPRESSOR
CONTACTOR 1
Y1
Y2
COMPRESSOR
1
CONTACTOR 2
L2
L1
(HOT)
SYSTEM COMPONENTS
1
HEAT RELAY 1
L2
L1
(HOT)
HEAT RELAY 2
FAN RELAY
FAN RELAY
1
COMPRESSOR
CONTACTOR 2
COMPRESSOR
CONTACTOR 1 M3955
L2
M3954
L2
L1
(HOT)