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

T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
THERMOSTAT
FALL
H1
FALL
H2
RISE
C1 ANTICIPATOR
CO
RISE
C1
CO
1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
2 ON MODELS INCLUDING EXTERNAL JUMPER, W2=W1 AND L=F.
Fig. 124. Schematic and hookup of T874J with Q674L. Used in heat pump applications.
60-2485—8
FAN
SWITCH
2
AUTO
3
ON
H1
ANTICIPATOR
4
H2
ANTICIPATOR
5
6
SYSTEM
8
SWITCH
EM. HT. OR
9
SUPL. HT.
HEAT
10
OFF
COOL
11
12
SUBBASE
R
Y
G
2
W2
EM. HT. OR
SUPL. HT.
LED (RED)
L
C
E
X
P
O
144
SYSTEM COMPONENTS
L1
L2
(HOT)
1
COMPRESSOR CONTACTOR
FAN RELAY
HEAT RELAY 1
OUTDOOR
THERMOSTAT
HEAT RELAY
HEAT RELAY 2
CONTACT 1
2
HEAT RELAY
CONTACT 2 HEAT RELAY 3
"X" RELAY
"P" RELAY
COOL
CHANGEOVER VALVE
M8003