Schematic And Hookup Of T874G With Q674F. Used In Heat Pump Applications; Schematic And Hookup Of T874D With Q674F. Used In Heat Pump Applications - Honeywell T874 Product Data

T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
THERMOSTAT
FALL
H1
H2
FALL
ANTICIPATOR
H2
FALL
CO
RISE
C1
Fig. 145. Schematic and hookup of T874G with Q674F. Used in heat pump applications.
THERMOSTAT
H1
FALL
H1 ANTICIPATOR
H2
FALL
C1
RISE
C1
ANTICIPATOR
C2
ANTICIPATOR
RISE
C2
Fig. 146. Schematic and hookup of T874D with Q674F. Used in heat pump applications.
60-2485—8
H1
ANTICIPATOR
1
2
4
SYSTEM
SWITCH
6
EM. HT.
8
9
C1 ANTICIPATOR
10
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND
OVERLOAD PROTECTION AS REQUIRED.
SUBBASE
1
3
FAN
SWITCH
4
AUTO
H2
ANTICIPATOR
ON
6
8
SYSTEM
SWITCH
OFF
SUPL. HT.
9
HEAT
10
AUTO
COOL
11
1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
SUBBASE
FAN
SWITCH
AUTO
ON
OFF
EM. HT.
LED (RED)
HEAT
AUTO
COOL
W1
Y1
RVR
G
R
W2
EHT
E
X
SUPL.
C
HEAT
LED
(RED)
Y2
158
SYSTEM COMPONENTS
(HOT) L1 L2
1
V
DEFROST
SUP. ELEC.
RELAY
HT. RELAY
Y
OUTDOOR
THERMOSTAT
TIME DELAY
EM. HT. RELAY FAN RELAY
FAN RELAY
F
EM. HT. RELAY
E
COOL CHANGEOVER
VALVE
R
COMPRESSOR
INTERNAL
CONTACTOR
THERMOSTAT
M
OVERLOAD
SYSTEM COMPONENTS
EHR
EHR REVERSING
RELAY
LPCO
COMPRESSOR
RVR
CONTACTOR 1
DFR 2
FAN RELAY
ODT 3
HEAT
RELAY 2
ODT 2
HEAT RELAY 1
HEAT RELAY 3
SUPL. HT.
RELAY
COMPRESSOR
DFR 2
CONTACTOR 2
HIGH
PRESSURE
SWITCH
M8375
L1
(HOT)
L2
1
M7010