Bryant Q674 Thermostat User Manual


 
T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
60-24858212
Fig. 228. Schematic and hookup of T874R with Q674L. Used in heat pump applications.
H1
FALL
C1
L1
(HOT)
L2
1
1
2
2
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
REMOVABLE JUMPER (INSTALLED).
THERMOSTAT
SUBBASE
SYSTEM COMPONENTS
H2
FALL
H1/C1 ANTICIPATOR
H2 ANTICIPATOR
RESET
EM. HT.
HEAT
OFF
COOL
AUX. HT.
LED
(GREEN)
EM. HT.
LED (YELLOW)
C815A OUTDOOR
THERMISTOR
COOL CHANGEOVER
VALVE
ELECTRIC
HEAT RELAY
ELECTRIC
HEAT RELAY
EM. HT.
O.D.S.
SERVICE
EM. HT. RELAY
FAN RELAY
COMP. RELAY O.L. IN. STAT. HI. PRO.
AUTO
ON
M3259
1
2
3
4
5
6
11
12
O
T
C
E
W1
L
G
Y1
R
SENSOR
LED (RED)
SYSTEM
SWITCH
FAN
SWITCH