T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
60-2485840
B1269 Whalen; Hi-Lo fan switch; constant fan in heat
and cool s
y
stem switch positions; used with
T872C1574.
None
B1277 S
q
uare D no. HCB-5. Q674B1034
B1285 Wards; RC-RH and F-W3
j
umpers; used with
T872C1673. Gas Furnace:
T874C1018/
Q674B1034
Electric Furnace:
T874C1018/
Q674B1075
Ad
j
ust anticipator
faster
for correct
performance.
B1293 Lennox no. 41C96; used with T872C1673. Same as
Q672B1285
Q672C S
y
stem: OFF-AUTO, Fan: AUTO-ON
C1003 Standard OEM Q674C1058
C1011 Westin
g
house; RC-RH
j
umper. Q674C1058 RC-RH
j
umper re
q
uired.
C1029 W1-Y2
j
umper; for heat pump; used with
T872D1136. Q674E1049 Replacement has heat/cool s
y
stem
switchin
g
.
C1037 Chr
y
sler Airtemp; S
y
stem: COOL-OFF-AUTO. Q674C1058
C1045 Westin
g
house; heat pump; used with
T872S1005. T874C1018/
Q674C1058 Wirin
g
differences
(
old=new
)
:
V=RC-RH, F=G, C=Y1, Z=B,
H2=W2; W1-Y1
j
umper re
q
uired.
C1052 Isolated sta
g
e 2 heat circuit for dc electric heat
rela
y
.Recontrol Use T874G1246/Q674F1212 which
adds HEAT-COOL-EM.HT. s
y
stem
switch.
C1060 Fedders special. Q674C1058
C1078 General Electric no. AY28X109. Q674C1058
C1086 Command-Aire; heat pump; used with
T872H1009. Y594H1012
C1102 TRADELINE Q674C1058
Q672D S
y
stem: None. Fan: None.
D1002 Standard OEM; used with T872F1126. Q674D1040
D1010 Lennox special. None
D1028 Carrier; RC-RH
j
umper. None
D1036 Carrier no. HH93AZ070; RC-RH
j
umper. Q674D1040 RC-RH
j
umper re
q
uired.
D1044 General Electric no. AY-28X100. None
D1069 S
q
uare D no. HCB-4. None
D1077 York; used with T872G1364. None
D1085 TRADELINE Q674D1040
Q672E S
y
stem: OFF-HEAT-AUTO-COOL
Fan: AUTO-ON
E1001 Standard OEM Q674E1049
E1019 Lennox no. P-8-8892; heat pump; cool mode
chan
g
eover; used with T872G1026. T874D1165/
Q674B1075
E1027 Heat pump circuit; W1-Y2
j
umper; cool mode
chan
g
eover; used with T872G1018. Y594G1393 Wirin
g
differences
(
old=new
)
: Y1=O,
Y2=Y.
E1035 Heat pump circuit; W1-Y2
j
umper; cool mode
chan
g
eover. Y594G1393 Wirin
g
differences
(
old=new
)
: Y1=O,
Y2=Y.
E1043 Heat pump circuit; heat mode chan
g
eover. Q674E1049 Wirin
g
differences
(
old=new
)
:
W1=B, W2=W1; W1-Y1
j
umper.
Table 7. Q672-Q674 Subbase Cross Reference.
Model Number Description Q674 Trade
ReplacementaRemarks
aWhen replacin
g
a T872 Thermostat and Q672 Subbase, alwa
y
s replace both the thermostat and subbase.