Schematic And Hookup Of T874S With Q674F. Used In Heat Pump Applications - Honeywell T874 Product Data

THERMOSTAT
H1 ANTICIPATOR
FALL
H1
C1
RISE
C1
ANTICIPATOR
C2
C2
ANTICIPATOR
RISE
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
Fig. 222. Schematic and hookup of T874B with Q674E. Used in standard applications.
THERMOSTAT
2
H1
FALL
H1 ANTICIPATOR
3
4
H2
H2 ANTICIPATOR
FALL
5
7
RISE
C1
8
9
C1
ANTICIPATOR
10
C2
C2
RISE
ANTICIPATOR
11
CO
RISE
1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
Fig. 223. Schematic and hookup of T874S with Q674F. Used in heat pump applications.
SUBBASE
2
3
FAN SWITCH
AUTO
4
ON
8
SYSTEM
SWITCH
OFF
9
HEAT
10
AUTO
COOL
11
FAN SWITCH
AUTO
ON
SYSTEM
SWITCH
OFF
EM. HT.
HEAT
AUTO
COOL
207
T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
SYSTEM COMPONENTS
R
L
G
W
MALFUNCTION
LED (RED)
C
HIGH SPEED
LED (YELLOW)
LOW
SPEED
LED
(GREEN)
Y1
Y2
SUBBASE
AUX. HT.
LED (RED)
MALFUNCTION
LED (RED)
HIGH SPEED
LED (YELLOW)
LOW SPEED
LED (GREEN)
L1
(HOT)
L2
SYSTEM
1
MONITOR
FAN RELAY
HEAT RELAY
COMPRESSOR
CONTACTOR 1
COMPRESSOR
CONTACTOR 2
M5920
SYSTEM COMPONENTS
L1
R (HOT)
L2
1
L
FAN RELAY
G
AUX. HT. RELAY
W2
E
EM.HT. RELAY
C
COMPRESSOR
CONTACTOR 1
Y1
COMPRESSOR
CONTACTOR 2
Y2
O
COOL
CHANGEOVER VALVE
M5923
60-2485—8