Honeywell T874 Product Data page 169

THERMOSTAT
H1 ANTICIPATOR
H1
FALL
H2
H2 ANTICIPATOR
FALL
CO
C1 ANTICIPATOR
RISE
C1
RISE
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
Fig. 161. Schematic and hookup of T874G with Q674J. Used in heat pump applications.
T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
SUBBASE
1
FAN
SWITCH
AUTO
ON
2
4
6
SYSTEM
SWITCH
8
SUPL. HT.
9
ON
OFF
10
2
N.O. SWITCH — INSTALLER ADDED, TO LIGHT EM. HT. LED
WHEN COMPRESSOR OPERATION IS NOT NORMAL.
169
SYSTEM COMPONENTS
COOL CHANGEOVER VALVE
O
G
R
OUTDOOR
THERMOSTAT
W 2
EM. HT. RELAY
CONTACT 1
E
EM. HT. RELAY
2
CONTACT 2
L
SUPL. HT.
LED (RED)
C
Y
1
L1
(HOT)
L2
FAN RELAY
EM. HT. RELAY 1
EM. HT. RELAY 2
EM.HT.
RELAY 3
COMPRESSOR
CONTACTOR 1
M5724
60-2485—8