Schematic And Hookup Of T874D With Q674E. Used In Standard Applications - Honeywell T874 Product Data

THERMOSTAT
3
H2
H1
FALL
ANTICIPATOR
RISE
CO
H1
C1
RISE
C1 ANTICIPATOR
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
1
2 JUMPER HONEYWELL SUPPLIED, FIELD INSTALLED.
3 H2 MAKE OFFEST 8˚ F BELOW H1 MAKE.
Fig. 97. Schematic and hookup of T874P with Q674C. Used in heat pump applications.
THERMOSTAT
1
H1 ANTICIPATOR
FALL
H1
4
FALL
H2 ANTICIPATOR
H2
C1
RISE
10
C1 ANTICIPATOR
RISE
11
C2
C2 ANTICIPATOR
2
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
2
T874A IS SINGLE-STAGE (NO W2 OR Y2).
Fig. 98. Schematic and hookup of T874D with Q674E. Used in standard applications.
1
2
FAN
3
SWITCH
4
AUTO
ON
5
6
SYSTEM SWITCH
8
OVERRIDE
AUTO
9
OFF
10
SUBBASE
FAN
SWITCH
AUTO
ON
6
SYSTEM
SWITCH
8
OFF
HEAT
AUTO
9
COOL
123
T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
SUBBASE
OVERRIDE
LED (RED) SERVICE
LED (RED)
SERVICE
LED (RED)
SYSTEM COMPONENTS
Y
COMPRESSOR CONTACTOR
G
FAN RELAY
C
CLOSED-DAY
OPEN-NITE
R
1
B
B RELAY
L
X
COMPRESSURE FAILURE
S
2
JUMPER
P
W
COOL CHANGEOVER VALVE
SYSTEM COMPONENTS
A
SYSTEM MONITOR
W1
HEAT RELAY 2
HEAT RELAY 1
W2
CHANGEOVER
RELAY
B
RH
RC
CHANGEOVER
RELAY
O
G
FAN RELAY
Y2
COMPRESSOR
CONTACTOR 1
COMPRESSOR
CONTACTOR 2
Y1
L2
L1
(HOT)
M100A
L2
1
L1
(HOT)
L1
(HOT)
L2
1
M5106A
60-2485—8