T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
60-2485—8 106
Fig. 63. Schematic and hookup of T874F with Q674D. Used in wood/coal applications.Fig. 64. Schematic and hookup of T874A with Q674Q. Used in fan coil applications.
L1
(HO
T)
L2
1
NO
SYSTEM
SWITCH
H2 ANTICIPATOR
H1
H2FALL
1POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
M3725
NO FAN
SWITCH
R
W2
H1 ANTICIPATOR
AUX. HT. RELAY
W1
C
WOOD/COAL
RELAY
FALL
YELLOW
GREEN
1
4
8
9
10
THERMOSTAT SUBBASE SYSTEM COMPONENTS
HEAT/COOL
SWITCH
H1
FALL
L1
(HOT)
L2
1
C1 RISE
M8005
2
1
2
H1
ANTICIPATOR
C1
ANTICIPATOR
5
4
2
1W1
B
R
G1
G2
O
Y1 HI
MED
LO
K2
K1
K2 K
2
K
1
COMPRESSOR CONTACTOR
O RELAY
K2 RELAY
K1 RELAY
B RELAY
HEAT RELAY 1
SYSTEM
SWITCHHEAT
OFF
COOL
FAN
SWITCH
LO
MED
HIGH
ON
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
SINGLE SETPOINT LEVER AND BIMETAL.
3
L2 L1
THERMOSTAT SUBBASE SYSTEM COMPONENT
3-SPEED FAN SCHEMATIC