Schematic And Hookup Of T874J, R With Q674L. Used In Heat Pump Applications - Honeywell T874 Product Data

T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
THERMOSTAT
H1/C1
ANTICIPATOR
FALL
H1
C1
FALL
H2
H2 ANTICIPATOR
POWER SUPPLY. PROVIDE DISCONNECT
1
MEANS AND OVERLOAD PROTECTION
AS REQUIRED.
2 FIELD WIRE JUMPER TO ALLOW SINGLE
SYSTEM TRANSFORMER.
Fig. 102. Schematic and hookup of T874J,R with Q674L. Used in heat pump applications.
60-2485—8
SUBBASE
1
FAN
SWITCH
2
AUTO
ON
3
4
5
6
SYSTEM
SWITCH
7
EM. HT.
HEAT
OFF
COOL
126
SYSTEM COMPONENTS
COMPRESSOR
OVERLOAD
CONTACTOR
SWITCH
M
F
V
OUTDOOR
THERMOSTAT
Y
EM. HT.
RELAY CONTACT
2
E
EM. HT.
LED (RED)
X
VR
R
L1 L2
1
(HOT)
HIGH
INTERNAL PRESSURE
SWITCH
THERMOSTAT
FAN RELAY
SUPPL. ELEC.
HT. RELAY
TIME DELAY
FAN RELAY
EM. HT. RELAY
COOL CHANGEOVER
VALVE
L1 L2 1
M4726
(HOT)