T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
60-2485—878
F1089 152 Obsolete. Includes EM HEAT LED; X2-E and RC-RH
j
umpers. Q674F1022
F1097 142 Obsolete. Southwest special; W2-X2
j
umper. Q674F1022
F1105 145 Obsolete. Lennox heat pump; EM HEAT LED; used
with T874G1154. Y594G1252aWirin
g
differences
(
old=new
)
:
V=R, Y=W2, F=G, X2=X,
R=O, M=Y; L-E
j
umper
re
q
uired.
F1113 150 Ob sole te. Lennox heat pump; part no. 24F6201; V-VR
j
umper; EM HEAT LED; chan
g
eover in coolin
g
; used
with T874G1014, G1022.
Y59461252aWirin
g
differences
(
old=new
)
:
R=O, M=Y, F=G, Y=WC,
V=VR=R; must use sin
g
le
transformer.
F1121 153 Obsolete. Westin
g
house heat pump; EM HEAT LED;
used with T874G1048. Y594G1252a
F1139 148 Obsolete. Tappan heat pump; EM HEAT LED; auto fan
in emer
g
enc
y
heat mode; used with T874G1147. Y594G1252aWirin
g
differences
(
old=new
)
:
C=X.
F1162 151 Obsolete. Crispaire heat pump; EM HEAT LED; used
with T874G. Y594G1393a
F1170 153 Obsolete. Heatwave
(
Southwest Mf
g
.
)
heat pump; EM
HT LED; used with T874G1105. Y594G1252a
F1188 153 Obsolete. Luxaire heat pump. Y594G1252a
F1196 178 Obsolete. Williamson; EM HEAT and SERVICE LEDs;
used with T874N1008; used in Y594N1007. Q674F1220
F1204 154 Obsolete. Special for Crispaire; EM HEAT and COMP
FAULT LEDs; used with T874G1089; used in
Y594G1153.
Y594G1393aWirin
g
differences
(
old=new
)
:
A=L.
F1212 155 Includes AUX HEAT and EM HEAT LEDs; used with
T874G1246, G1451, G1592, G1915; used in
Y594G1252.
Q674F1212 or
Y594G1252a
F1220 178 Used with T874N1016; used in Y594N. Q674F1220
F1238 155 Obsolete. Rheem part no. 41-20797-14; AUX HEAT
and EM HEAT LEDs; used with T874G1097, G1212,
G1220, G1238.
Y594G1252a
F1246 156 Obsolete. Westin
g
house heat pump; EM HEAT and
AUX HEAT LEDs; auto fan in emer
g
enc
y
heat mode;
chan
g
eover in coolin
g
mode.
Y594G1252a
F1253 157 Obsolete. Wesco/Addison heat pump; used with
T874G1261, G1279, G1287. Y594G1252aWirin
g
differences
(
old=new
)
:
Y1=O, C=X, W1=Y, X=L.
F1261 179 Includes two LEDs; used with T874N1024; used in
Y594N. Y594G1419aWirin
g
differences
(
old=new
)
:
L=X2, Y=Y1.
F1279 158 Obsolete. Westin
g
house heat pump; two LEDs; used
with T874G. Y594G1252aWirin
g
differences
(
old=new
)
:
L1=L.
F1295 147 Obsolete. Keeprite/Westin
g
house heat pump;
SERVICE, AUX HEAT and EM HEAT LEDs; used with
T874G1188.
Y594G1252aWirin
g
differences
(
old=new
)
:
S=L; replacement does not
include A or T terminals.
F1311 155 York heat pump; AUX HEAT and EM HEAT LEDs; used
with T874G1410. Y594G1252a
F1329 142 Obsolete. Heil Quaker part no. HQ712005HW; one
LED and field selectable inserts. Q674F1022
F1337 166 Obsolete. WeatherKin
g
heat pump; two LEDs and field
selectable inserts; used with T874D1009; used in
Y594D1222.
Q674F1022 Wirin
g
differences
(
old=new
)
:
R=RC-RH; replacement has
no LEDs.
Table 9. Q674 Subbase Cross Reference.
Model
Number Fig.
No. Description Q674 Trade
Replacement Remarks
aBoth the thermostat and subbase must be repl aced.