Filter
Top Products
T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
60-2485—8144
Fig. 124. Schematic and hookup of T874J with Q674L. Used in heat pump applications.
H1
FALL
C1
RISE
CO
H2
FALL
CO
RISE
L1
(HOT)
L2
1
THERMOSTAT SUBBASE
SYSTEM COMPONENTS
COMPRESSOR CONTACTOR
FAN RELAY
HEAT RELAY 1
OUTDOOR
THERMOSTAT
HEAT RELAY
CONTACT 1
HEAT RELAY 2
HEAT RELAY
CONTACT 2 HEAT RELAY 3
"X" RELAY
"P" RELAY
COOL
CHANGEOVER VALVE
SYSTEM
SWITCH
EM. HT. OR
SUPL. HT.
HEAT
OFF
FAN
SWITCH
AUTO
ON
H1
ANTICIPATOR
H2
ANTICIPATOR
C1 ANTICIPATOR
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
ON MODELS INCLUDING EXTERNAL JUMPER, W2=W1 AND L=F.
1
3
4
5
6
8
9
10
11
O
P
X
E
C
L
G
Y
R
2
W2
EM. HT. OR
SUPL. HT.
LED (RED)
M8003
2
COOL
2
12
2