Honeywell T874 - Schematic and Hookup of T874 C, D with Q674 F. Used in Standard Applications

T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
60-2485—8 156
Fig. 141. Schematic and hookup of T874C with Q674F. Used in standard applications.
Fig. 142. Schematic and hookup of T874C,D with Q674F. Used in standard applications.
H1
FALL
H2
FALL
C1
RISE
L1
(HOT
)
L2
1
H1
ANTICIPATOR
4
1
C2
RISE
C1
ANTICIPATOR
C2
ANTICIPATOR
8
9
10
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND
OVERLOAD PROTECTION AS REQUIRED.
1
R
AUTO
ON
FAN
SWITCH
SYSTEM
SWITCH
OFF
EM. HT.
HEAT
AUTO
COOL
HEAT RELAY 1
HEAT RELAY 2
EM. HT. LED
(RED)
EM. HT. RELAY
FAN RELAY
COMPRESSOR
CONTACTOR 1
COMPRESSOR
CONTACTOR 2
M8376
THERMOSTAT
SUBBASE
SYSTEM COMPONENTS
E
G
Y2
Y1
6
11
X2
W2
W1
H2
ANTICIPATOR
H1
FALL
1
EM. HT.
HEAT
SYSTEM
SWITCH
H1 ANTICIPATOR
H2 ANTICIPATOR
C1
ANTICIPATOR
C2
ANTICIPATOR
AUTO
COOL
W2
M5985
POWER SUPPLY. PROVIDE DISCONECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
1
SYSTEM COMPONENTSSUBBASE
THERMOSTAT
4
6
8
9
10
11
OFF
AUTO
ON
FAN
SWITCH
L1
(HOT)
L2
1
B
X2
X1
E
G
O
Y2
Y1
R
EM. HT. RELAY
FAN RELAY
COMPRESSOR
CONTACTOR 2
COMPRESSOR
CONTACTOR 1
W1
HEAT RELAY 1
HEAT RELAY 2
C1
C2
RISE
RISE
H2
FALL
CHECK
LED (RED)