Honeywell T874 - Page 40

T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
60-2485—8 40
B1269 Whalen; Hi-Lo fan switch; constant fan in heat
and cool system switch positions; used with
T872C1574.
None
B1277 Square D no. HCB-5. Q674B1034
B1285 Wards; RC-RH and F-W3 jumpers; used with
T872C1673.
Gas Furnace:
T874C1018/
Q674B1034
Electric Furnace:
T874C1018/
Q674B1075
Adjust anticipator faster for correct
performance.
B1293 Lennox no. 41C96; used with T872C1673. Same as
Q672B1285
Q672C System: OFF-AUTO, Fan: AUTO-ON
C1003 Standard OEM Q674C1058
C1011 Westinghouse; RC-RH jumper. Q674C1058 RC-RH jumper required.
C1029 W1-Y2 jumper; for heat pump; used with
T872D1136.
Q674E1049 Replacement has heat/cool system
switching.
C1037 Chrysler Airtemp; System: COOL-OFF-AUTO. Q674C1058
C1045 Westinghouse; heat pump; used with
T872S1005.
T874C1018/
Q674C1058
Wiring differences (old=new):
V=RC-RH, F=G, C=Y1, Z=B,
H2=W2; W1-Y1 jumper required.
C1052 Isolated stage 2 heat circuit for dc electric heat
relay.
Recontrol Use T874G1246/Q674F1212 which
adds HEAT-COOL-EM.HT. system
switch.
C1060 Fedders special. Q674C1058
C1078 General Electric no. AY28X109. Q674C1058
C1086 Command-Aire; heat pump; used with
T872H1009.
Y594H1012
C1102 TRADELINE Q674C1058
Q672D System: None. Fan: None.
D1002 Standard OEM; used with T872F1126. Q674D1040
D1010 Lennox special. None
D1028 Carrier; RC-RH jumper. None
D1036 Carrier no. HH93AZ070; RC-RH jumper. Q674D1040 RC-RH jumper required.
D1044 General Electric no. AY-28X100. None
D1069 Square D no. HCB-4. None
D1077 York; used with T872G1364. None
D1085 TRADELINE Q674D1040
Q672E System: OFF-HEAT-AUTO-COOL
Fan: AUTO-ON
E1001 Standard OEM Q674E1049
E1019 Lennox no. P-8-8892; heat pump; cool mode
changeover; used with T872G1026.
T874D1165/
Q674B1075
E1027 Heat pump circuit; W1-Y2 jumper; cool mode
changeover; used with T872G1018.
Y594G1393 Wiring differences (old=new): Y1=O,
Y2=Y.
E1035 Heat pump circuit; W1-Y2 jumper; cool mode
changeover.
Y594G1393 Wiring differences (old=new): Y1=O,
Y2=Y.
E1043 Heat pump circuit; heat mode changeover. Q674E1049 Wiring differences (old=new):
W1=B, W2=W1; W1-Y1 jumper.
Table 7. Q672-Q674 Subbase Cross Reference.
Model Number Description
Q674 Trade
Replacement
a
Remarks
a
When replacing a T872 Thermostat and Q672 Subbase, always replace both the thermostat and subbase.