T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
79 60-24858
F1345 194 Obsolete. Addison heat pump; EM HEAT and CHECK
LEDs; used with T874G; used in Y594G. Y594G1252aWirin
g
differences
(
old=new
)
:
Y1=O, C=X, W1=Y, X=L.
F1360 167 Obsolete. Rheem part no. 41-20797-17; AUX HEAT
and EM HEAT LEDs; used with T874G1493. Y594G1526a
F1378 195 Obsolete. Includes EM HEAT and AUX HEAT LEDs;
used with T874G1501. Y594G1252aWirin
g
differences
(
old=new
)
:
L1=L; chan
g
eover in coolin
g
onl
y
.
F1394 139 Obsolete. Nepco heat pump; HEAT PUMP and AUX
HEAT LEDs; S
y
stem: AUX HEAT-HEAT PUMP-2
STAGE HEAT-OFF-COOL; used with T874D1595.
T874D1165/
Q674B1018a
Replacement has HEAT-OFF-
COOL s
y
stem switchin
g
and
no LEDs.
F1402 169 Obsolete. Coleman heat pump; two LEDs; used with
T874G1576; used in Y594G1377. Y594G1633a
F1410 170 Used with T874G1246, G1915; used in Y594G1393. Y594G1393a
F1428 199 Obsolete. Used with T874G1600; used in Y594G1401. Y594G1419aWirin
g
differences
(
old=new
)
:
j
umper W1-Y1.
F1436 167 Includes AUX HEAT and EM HEAT LEDs; chan
g
eover
in heatin
g
mode; used with T874G1626; used in
Y594G1526.
None
F1444 227 Includes AUX HEAT, EM HEAT and CHECK LEDs;
used with T874G1642; used in Y594G1419. Y594G1419a
F1451 204 Obsolete. York part no. 2TB047700524A; one LED and
field selectable inserts. Q674F1012 Wirin
g
differences
(
old=new
)
:
X2=X; X1=B.
F1477 227 TRADELINE;
g
ra
y
color; used with T874G1741,
G1824; used in Y594G1476, G1534. Y594G1476a
F1485 211 Trol-A-Temp b
y
Hone
y
well; chan
g
eover is provided b
y
Trol-A-Temp zone panel; used with T874G1758; used
in Y594G1492.
None See Trol-A-Temp.
F1501 223 Obsolete. Carrier two-speed compressor heat pump;
used with T874S1001. T8611M2025
(
pro
g
rammable
)
Includes ni
g
ht setback.
F1519 231 Obsolete. Nord
y
ne; used with T874G1832, G1840;
used in Y594G1542, G1559. Y594G1252aReplacement has auto
chan
g
eover in coolin
g
mode
onl
y
.
F1535 229 Obsolete. Lennox heat pump;
g
ra
y
color; used with
T874G1857; used in Y594G1583. Y594G1161aWirin
g
differences
(
old=new
)
:
E=X2, C=B, L=F.
F1543 204 Obsolete. TRADELINE Q674F1022 Wirin
g
differences
(
old=new
)
:
X2=X, X1=B.
F1550 243 Obsolete. Amana part no. 10573901; includes two
LEDs; used with T874G1899; used in Y594G1591. Y594G163 3
F1568 155 Obsolete. Gra
y
color; includes two LEDs; used with
onl
y
T874G1931. Y594G1476 Y1-W1
j
umper re
q
uired.
F1584 169 TRADELINE; includes two LEDs; used with
T874G1972; used in Y594G1633. Direct replacement
for Coleman/Evcon Y594G1377
(
T874G1576/
Q674D1402
)
; Coleman part no. 3600-373.
Y594G1633a
F1592 238 Heat Controller; Fan: AUTO-ON; S
y
stem: AUX HEAT-
HEAT PUMP- 2 STAGE HEAT-OFF-COOL; includes
two LEDs; used with T874C1844; used in Y594C1413.
Y594R1425 E-W2
j
umper re
q
uired; s
y
stem
switch: EM.HT.-HEAT-OFF-
COOL.
F1600 169 Obsolete. Amana part no. 10573903; includes two
LEDs; used with T874G1980; used in Y594G1641. Y594G163 3 Wirin
g
differences
(
old=new
)
;
W3=W2.
F1634 139 Standard OEM; S
y
stem: AUX HEAT-HEAT PUMP-
2 STG HEAT-OFF-COOL; includes two LEDs; used
with T874D2155.
Y594G1716
Table 9. Q674 Subbase Cross Reference.
Model
Number Fig.
No. Description Q674 Trade
Replacement Remarks
aBoth the thermostat and subbase must be repl aced.