Honeywell Q674L User Manual
Page 5
69-0392—9
5
T874R THERMOSTATS AND Q674L SUBBASES
Fig. 7. Internal schematic and typical wiring diagram for Y594R1300 (T874R1475/Q674L1520); fixed anticipation.
H2
FALL
H1
FALL
C1
L1
(HOT)
L2
1
2
2
1
2
POWER SUPPLY. PROVIDE
DISCONNECT MEANS AND
OVERLOAD PROTECTION
AS REQUIRED.
CONNECT CHANGEOVER
RELAY TO B FOR HEAT
CHANGEOVER, TO O FOR
COOL CHANGEOVER.
THERMOSTAT
SUBBASE
SYSTEM COMPONENTS
LACO
CHP
ODT 1
RTD 1
EHR 1
RTD 2
ODT 2
EHR 2
RTD 3
COMPRESSOR
MONITOR
R
L
X
W2
G
O
E
Y
B
HEAT
CHANGEOVER VALVE
COMPRESSOR
CONTACTOR
EM. HT. RELAY
COOL
CHANGEOVER VALVE
FAN RELAY
RTD 1
RD
10
8
H2
ANTICIPATOR
6
5
4
3
2
H1/C1
ANTICIAPTOR
FAN
SWITCH
AUTO
ON
SYSTEM
SWITCH
EM. HT.
HEAT
OFF
COOL
EM. HT.
LED (RED)
AUX. HT.
LED
(GREEN)
M1030A
H1
FALL
C
L1
(HOT)
L2
1
EM. HT.
LED (RED)
AUX. HT.
LED (GRN)
W3
O
L
G
R
W2
E
X
X2
B
W1
Y
AUX. HT. RELAY
EM. HT. RELAY
HEAT
CHANGEOVER
VALVE
W1 RELAY
COMPRESSOR
RELAY
W3 RELAY
COOL CHANGEOVER
VALVE
COMPRESSOR
MONITOR
FAN RELAY
H2
FALL
H1
ANTICIPATOR
C ANTICIPATOR
H2
ANTICIPATOR
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
REMOVE JUMPER WHEN W1 RELAY IS USED.
FACTORY-INSTALLED JUMPER.
1
M5067
FAN
SWITCH
AUTO
ON
SYSTEM
SWITCH
EM. HT.
HEAT
OFF
COOL
3
2
2
3
THERMOSTAT
SUBBASE
SYSTEM COMPONENTS
1
2
3
4
5
6
11
Fig. 8. Internal schematic and typical wiring diagram for Y594R1425 (T874R1616/Q674L1587). SUPER
TRADELINE
®
; universal model for heat, cool, or first stage heating changeover systems.
CHECK LED has isolated terminals for use in all systems.