T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
73 60-24858
B1554 82 Obsolete. TRADELINE; includes LOCKOUT LED and
removable
j
umpers between RC and RH terminals;
used with T874C1877; used in Y594C1421.
Y594D1347 Jumper RH-RC; s
y
stem
switch: Off-HEAT-AUTO-
COOL.
B1562 45 Obsolete. Amana lo
g
o; part no. P1217701F;
removable
j
umpers between RC and RH terminals. Q674B1034
B1570 45 Obsolete. Armstron
g
lo
g
o; part no. 03299A18. Q674B1034 Replacement is bei
g
e.
B1588 45 Obsolete. Standard OEM. Q674B1034 Replacement is bei
g
e.
Q674C S
y
stem: OFF-AUTO; Fan: AUTO-ON
C1009 72 Standard OEM; used with T874D1082; used in
Y594D1024. Q674C1058
C1017 Obsolete. Includes factor
y
-installed RC-RH
j
umper;
used with T874A,F,Q. Q674C1058
C1033 72 Trane part no. BAY28X187. Q674C1058
C1041 74 Obsolete. Command Aire heat pump; used with
T874H1005, H1054. Y594H1012aWirin
g
differences
(
old=new
)
:
Y1=O, Y2=Y; W-Y
j
umper
re
q
uired.
C1058 72 TRADELINE Q674C1058
C1066 73 Obsolete. Command Aire heat pump; used with
T874G1352. Y594H1012aWirin
g
differences
(
old=new
)
:
Y1=O, Y2=Y, L=R, R=none; R-
L
j
umper re
q
uired; no ni
g
ht
setback.
T8600D2028
(
pro
g
rammable
)
Wirin
g
differences
(
old=new
)
:
Y1=O, Y2=Y, L=R; W-Y
j
umper re
q
uired; ni
g
ht
setback.
C1074 81 Obsolete. Used with T874C1018. Q674C1058 Jumper W2-Y1 and RH-RC.
C1090 77 Obsolete. LSI-Mammoth heat pump; used with
T874K1001. Y594R1419aWirin
g
differences
(
old=new
)
:
RH-RC=R, W1=B, W3=W2,
W2=W1; remove Y1-W1
j
umper.
C1108 143 Obsolete. Northrup special; AUX HEAT LED; used with
T874G1139. Y594R1243aWirin
g
differences
(
old=new
)
:
Y1=Y, W1=W2, C=X.
C1116 76 Obsolete. McQua
y
part no. 02005959; two LEDs; used
with T874D1116. Q674C1058 Replacement has no LEDs.
C1124 79 Obsolete. LSI-Mammoth heat pump; RESET LED;
used with T874G-H; used in Y594G-H. Y594G1294
T8600D2028
C1132 75 Obsolete. McQua
y
part no. 03005049; sprin
g
return
momentar
y
s
y
stem switch position; used with
T874A1283.
See OEM for
replacement.
C1140 78 Obsolete. McQua
y
no. 860-442728B-00; S
y
stem:
OVERRIDE-AUTO-OFF; used with T874P1006. T8600D2028
(
pro
g
rammable
)
Wirin
g
differences
(
old=new
)
:
L=R, W=O; W-Y
j
umper
re
q
uired; ni
g
ht setback.
C1157 72 Obsolete. York part no. 2TB04700124A. Q674C1058
C1165 192 Obsolete. McQua
y
part no. 03005050; sprin
g
return
momentar
y
s
y
stem switch position. See OEM for
replacement.
C1173 96 Obsolete. American Air Filter part no. 4ELN-8787;
used with T874C1133. Q674C1058 Replacement has no LEDs.
C1181 76 Obsolete. California heat pump; used with T874C1000. Q674C1058
C1199 163 Obsolete. American Air Filter part no. 4ELN-8788; two
LEDs; sprin
g
return momentar
y
s
y
stem switch position;
used with T874G1485, G1535.
T8600D2028 No momentar
y
reset switch.
Table 9. Q674 Subbase Cross Reference.
Model
Number Fig.
No. Description Q674 Trade
Replacement Remarks
aBoth the thermostat and subbase must be repl aced.