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T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
60-2485—874
C1207 78 Obsolete. Friedrich; S
stem: OVERRIDE-AUTO-OFF;
used with T874P1014.
T8600D2028
pro
rammable
Wirin
differences
old=new
:
L=R, W=O; W-Y
umper
re
uired; ni
ht setback.
C1215 97 Obsolete. Friedrich part no. AQ5315; S
stem:
OVERRIDE-AUTO-OFF; OVERRIDE and SERVICE
LEDs; used with T874P1022, P1030.
T8600D2028
pro
rammable
Wirin
differences
old=new
:
L=R, W=O; W-Y
umper
re
uired; ni
ht setback.
C1223 73 Obsolete
. Friedrich part no. AQ5323; used on s
stems
re
uirin
ni
ht setback contacts; used with
T874G1584.
Y594H1012
a
Wirin
differences
old=new
:
Y1=O, Y2=Y, L=R, R=none; R-
L
umper re
uired; no ni
ht
setback.
T8600D2028
pro
rammable
Wirin
differences
old=new
:
L=R, W=O; W-Y
umper
re
uired; ni
ht setback.
C1249 164 Includes MALFUNCTION LED; used with T874H1062;
used in Y594H1012.
Y594H1012
a
C1256 73 Obsolete. Used with T874G1618.
Y594H1012
a
Wirin
differences
old=new
:
Y1=O, Y2=Y, L=R, R=none; R-
L
umper re
uired; no ni
ht
setback.
T8600D2028
pro
rammable
Wirin
differences
old=new
:
L=R, W=O; W-Y
umper
re
uired; ni
ht setback.
C1264 165 Obsolete. Carrier part no. HH93AZ193; used with
T874L1018
HH07AT178
.
See OEM for
replacement.
C1280 181,
203
Obsolete. McQua
heat pump; part no. 60687401;
COMP FAULT LED; used with T874K1019, L1034.
T8600D2028 See thermostat description for
replacement information.
C1298 76,
225
Obsolete
. McQua
part no. 60684801; SERVICE LED;
used with T874A1523, A1549, D1918.
See OEM for
replacement.
C1306 75 Obsolete
. McQua
part no. 60685001; SERVICE LED;
sprin
return momentar
s
stem switch position; used
with T874A1325.
See OEM for
replacement.
C1314 72 Obsolete
. Trane part no. BAS-0429; used with T874A-F. Q674C1058
C1322 173 Obsolete. Carrier part no. HH93AZ199; FAULT and CK
FILTER LEDs; used with T874H1070
HH07AT166
,
T874H1088
HH07AT167
or T874H1153
HH07AT167
; used in Y594H1053.
Y594H1012
a
Wirin
differences
old=new
:
2=X.
C1330 177 Obsolete
. LSI-Mammoth part no. 71115201; RESET
LED; used on s
stems with ni
ht setback contacts;
used with T874G1659, H1096; used in Y594G1427,
H1020.
Y594H1012
a
Wirin
differences
old=new
:
R1=R; R2=L.
C1355 74 Friedrich part no. AQ355; SERVICE LED; used with
T874H1112.
Y594H1012
a
Wirin
differences
old=new
:
Y1=O, Y2=Y; L-R
umper
re
uired.
C1363 99 Obsolete. McQua
part no. 61202601; SERVICE LED;
auto fan in heat and cool mode; used with T874C.
T874C1125/
Q674B1075
a
Replacement has HEAT-OFF-
COOL.
219 Obsolete. Used with T874C. See OEM for
replacement.
220 Obsolete
. Used with T874W. See OEM for
replacement.
100 Obsolete
. Used with T874W. T8611M2025
pro
rammable
Includes ni
ht setback.
C1371 72 American Standard part no. ASYSTAT616. Q674C1058
Table 9. Q674 Subbase Cross Reference.
Model
Number
Fig.
No. Description
Q674 Trade
Replacement Remarks
a
Both the thermostat and subbase must be replaced.