Honeywell T874 Product Data

T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
60-2485—8 172
Fig. 164. Schematic and hookup of T874H with Q674C. Used in standard applications.
Fig. 165. Schematic and hookup of T874L with Q674C. Used in heat pump applications.
H1
FALL
L1
(HOT)
L2
1
2
OFF
FAN SWITCH
SYSTEM SWITCH
C1
ANTICIPATOR
AUTO
ON
M5726
POWER SUPPLY. PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
1
SYSTEM COMPONENTSSUBBASETHERMOSTAT
3
4
6
8
9
10
O
Y
G
R
L
B
X
2
AUTO
CO
RISE
C1
RISE
R-L JUMPER SUPPLIED BY HONEYWELL.
2
H1
ANTICIPATOR
MALFUNCTION
LED (RED)
HEAT CHANGEOVER
VALVE
MALFUNCTION
SWITCH
FAN RELAY
COMPRESSOR
CONTACTOR
COOL CHANGEOVER
VALVE
L1
(HOT)
L2
1
RISE
C1
H1 ANTICIPATOR
1
FAN
SWITCH
ON
AUTO
M572
7
POWER SUPPLY. PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
1
SYSTEM COMPONENTS
SUBBASETHERMOSTAT
SYSTEM
SWITCH
AUTO
OFF
2
3
4
5
7
8
9
10
H2 ANTICIPATOR
J
S
G
C
R
O
H
2
H
1
FIELD REMOVABLE JUMPER.
2
H1 AND C1 ARE DPST SWITCHES.
3
H2
FALL
H1
FALL
3
3
2
C1
ANTICIPATOR
R1 N.O.2
S1 RELAY
SOLENOID RELAY S1 N.C.
FAN RELAY
AUX. HT. RELAY
R1 N.C.1
COMPRESSOR
CONTACTOR
R2 N.O. 1
R1 RELAY
REV. VALVE

Honeywell T874 Specifications

General

Brand	Honeywell
Model	T874
Category	Thermostat
Language	English