Honeywell T874 - Schematic and Hookup of T874 P, D, F with Q674 B. Used in Pump Applications; Schematic and Hookup of T874 G with Q674 D. Used in Standard Applications

T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
103 60-2485—8
Fig. 57. Schematic and hookup of T874P with Q674B. Used in heat pump applications.
Fig. 58. Schematic and hookup of T874G with Q674D. Used in standard applications.
H2
FALL
H1
RISE
CO
L1
(HOT
)
L2
1
C1
RISE
2
1
2
POWERSUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
JUMPER HONEYWELL SUPPLIED, FIELD INSTALLED.
C1 ANTICIPATOR
H1 ANTICIPATOR
FAN SWITCH
AUTO
ON
SYSTEM
SWITCH
OVERRIDE
HEAT
OFF
COOL
1
2
3
4
5
6
8
9
10
T
W
P
S
L
B
R
G
Y
COMPRESSOR
CONTACTOR
FAN RELAY
CLOSED-DAY
OPEN-NITE
B RELAY
JUMPER
COOL CHANGEOVER
VALVE
M8004
THERMOSTAT SUBBASE SYSTEM COMPONENTS
H1 ANTICIPATOR
H1
FALL
M372
2
C1
H2 ANTICIPATOR
H2
FALL
ECONOMIZER
PACKAGE
RISE
RISE
CO
C1 ANTICIPATOR
CONTROL
PANEL
W
RH
B
RC
Y
O
O
W2
O
Y
THERMOSTAT
SUBBASE SYSTEM COMPONENTS
2
3
4
6
8
9
10
NO FAN
SWITCH
NO SYSTEM
SWITCH