Schematic And Hookup Of T874N With Q674F. Used In Heat Pump Applications - Honeywell T874 Product Data

T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
THERMOSTAT
H1
ANTICIPATOR
H1
FALL
H2
ANTICIPATOR
H2
FALL
RISE
C1
ANTICIPATOR
C1
CO
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
1
Fig. 179. Schematic and hookup of T874N with Q674F. Used in heat pump applications.
60-2485—8
SUBBASE
1
2
4
FAN SWITCH
AUTO
ON
5
6
SYSTEM
SWITCH
OFF
EM. HT.
8
HEAT
AUTO
9
COOL
10
W1
DEFROST
RELAY
EM.HT. RELAY
CONTACT
EM.HT. RELAY
CONTACT
W3
G
R
W2
E
EM. HT.
LED (RED)
X
CHECK
LED
(GREEN)
L
HIGH
PRESSURE
SWITCH
Y
182
SYSTEM COMPONENTS
OUTDOOR
THERMOSTAT REVERSING
VALVE
HEAT
RELAY 2
HEAT
RELAY 3
FAN RELAY
1
L1
(HOT)
L2
HEAT
RELAY 1
EM. HT.
RELAY
OPTIONAL
COMPRESSOR
FAILURE DEVICE
COMPRESSOR
CONTACTOR
M3686