Bryant T874 Thermostat User Manual


 
T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
60-24858102
Fig. 55. Schematic and hookup of T874A,D,F with Q674D. Used in standard applications.
Fig. 56. Schematic and hookup of T874C with Q674B. Used in standard applications.
M3667A
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
JUMPER RC, RH FOR SINGLE TRANSFORMER.
B AND 5 TERMINALS AVAILABLE ON SOME MODELS.
COMPRESSOR
CONTACTOR 1
H2 ANTICIPATOR
C1
C1 ANTICIPATOR
C2
H1 ANTICIPATOR
H1
HEAT RELAY 1
HEAT RELAY 2
COMPRESSOR
CONTACTOR 2
FALL
L1
(HOT)
L2
RH
W2
Y2
Y1
L1
(HOT)
L2
RC
FALL
H2
RISE
C2 ANTICIPATOR
RISE
NO
FAN
SWITCH
NO
SYSTEM
SWITCH
W1
B
1
1
3
2
3
2
1
4
5
6
8
9
10
11
3
THERMOSTAT
SUBBASE
SYSTEM COMPONENTS
H1
FALL
L1
(HOT)
L2
1
H2
FALL
C1
RISE
FAN
SWITCH
SYSTEM
SWITCH
AUTO
ON
HEAT
OFF
COOL
COMPRESSOR
CONTACTOR 1
O RELAY
B RELAY
AUX. HT. RELAY
FAN RELAY
RESET
RESET
LED (RED)
C1 ANTICIPATOR
H2 ANTICIPATOR
H1 ANTICIPATOR
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
1
4
6
8
9
10
11
Y1
Y2
O
B
W2
R
G
X
1
SUBBASE
SYSTEM COMPONENTS
M5975