T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
60-2485—842
F1125 BDP no. 3442DP90; used with T872G1117,
G1166, G1174. Y594G1252 Wirin
g
differences
(
old=new
)
: C=X.
F1133 Williamson; heat pump; EM. HT. LED; heat
mode chan
g
eover; compressor lockout in
EM. HT.; used with T872N1010.
T874N1016/
Q674F1220
F1141 Westin
g
house; EM. HT. LED; auto fan in
EM. HT.; used with T872G1034. Y594G1252 Wirin
g
differences
(
old=new
)
:
W=W2.
F1158 Rheem Ruud; heat pump; EM. HT. LED; cool
mode chan
g
eover; compressor lockout in
EM. HT.; used with T872G1083, G1133, G1141;
auto fan in EM. HT.
Y594G1252
F1166 Crispaire; EM. HT. LED; used with T872G1208. Y594G1252
F1174 Carrier no. HH93AZ081; EM. HT. LED. Q674F1022
F1182 S
q
uare D no. HCB-1; Chek Lite; R-X2
j
umper;
S
y
stem: Aux. Heat replaces EM. HT. Q674F1022 R-X2
j
umper; add monitor switch
between X1 and low side of power.
F1190 EM. HT. LED; X2-E and RC-RH
j
umpers. None
F1208 TRADELINE; cool mode chan
g
eover; EM. HT.
LED; used with T872G1224. Y594G1419
F1216 TRADELINE; heat mode chan
g
eover; EM. HT.
LED; used with T872N1028. T874N1016/
Q674F1220
F1224 Heatwave
(
Southwest Mf
g
.
)
; compressor
lockout in EM. HT.; EM. HT. LED; used with
T872G1232.
Y594G1252
F1232 Rheem; cool mode chan
g
eover; EM. HT. and
AUX. HEAT LEDs; compressor lockout in
EM. HT.; used with T872G1133.
Y594G1252
F1240 Lennox; cool mode chan
g
eover; EM. HT. and
SERVICE LEDs; used with T872G1240. None
F1257 Westin
g
house; cool mode chan
g
eover;
EM. HT. and AUX. HEAT LEDs; auto fan in
EM. HT; used with T872G1034.
Y594G1252 Wirin
g
differences
(
old=new
)
:
W=W2.
F1265 Wesco Addison; Chek and EM. HT. LEDs; used
with T872G1281, G1265. Y594G1252 Wirin
g
differences
(
old=new
)
: C=X.
F1273 Southwest special; no. 0361-136; W2-X2
j
umper. None
F1281 Luxaire special; used with T872G1315. Y594G1252
F1299 Bard special; used with T872N1036, N1044. T874N1016/
Q674F1220
F1315 Williamson special; used with T872N1010. T874N1016/
Q674F1220
F1323 Crispaire special; used with T872G1208. Y594G1252
Q672G S
y
stem: OFF-AUTO. Fan: None.
G1009 Standard OEM Q674G1070
G1017 Sin
g
er; O-B
j
umper; used with T872D1375. Q674G1070
G1025 Includes O and B terminals. Q674G1070
G1033 General Electric no. AY28X102. Q674G1070
G1041 Sin
g
er no. 02005649; French wordin
g
; O-B
j
umper. Q674G1070 Less French wordin
g
.
G1066 SLI-Mammoth; heat pump; heat mode
chan
g
eover. Q674G1070 Connect fan
(
G
)
wire to Y1 terminal;
B-O and RC-RH
j
umpers.
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.