Honeywell Heat/1Cool - T841A1563 Premier 2 Stage Thermostat User Manual page 68

HONEYWELL
HEATING CHANGEOVER
Existing
Function
Terminals
Common
X
Power
R
or or
Compressor
Y1 Y C
1st Stage
–
Heat
Aux. Heat
W2
Fan
G
C/O Valve
W1
Heat
C/O Valve
–
Cool
System
L
Monitor
or
Em. Heat
E K
Multiple Aux.
Heat Loads
W3
LED Indication
–
2nd Stage
–
Compressor
2nd Stage
–
Cool
Configure O/B (select models) in Installer Setup.
When W2 is not used, configure W2 cycle rate to NC.
Terminal is for multiple second stage heating loads such as contactors,
sequencers, or relays.
Leave factory-installed jumper in place.
Terminal X (C) must be connected to transformer common.
If multiple auxiliary heat loads are used, connect to W2 (Aux W8900B)
terminal.
70-6627 • 66
Electromechanical
X X X
R R R
Y Y Y1
– W1 W1
W2 W2 W2
G G G
B B B
O O O
L
E E E
W3 W3 W3
– X2 X1 X2
– – –
– – –
TYPICAL THERMOSTATS AND SUBBASES — HONEYWELL MODEL NUMBER
T872N1002/Q672F1133
T874N1016/Q674F1220
Electronic Replacement or Upgrade
Chronotherm ®
III
C C
R R
or
Y1 Y Y
W1 W1
W2 W2
G G
B B
O O O
L L
E E
X1 X2 –
– –
– –
Optional CHECK LED on T8611G1004. See Fig. 26.
Field-installed X2 to X jumper (provided).
Optional LED indication activated with completed circuit on X1 and
X2 terminals.
LED is energized when terminal is powered.
L terminal is powered continuously when thermostat is in Em. Ht. position.
T872N1028/Q672F1216
T874N1040/Q674F1261
Chronotherm
IV
C C C
R R R
Y1 Y Y1
W1 W1 W1
W2 W2 W2
G G G
or or
B O/B B B
or or
O/B O O
L L L
E E E
– – X1 X2
– – –
– – –
C
R
Y1/W1
–
Aux.
G
O/B O/B
O/B O/B
L
E
–
W2
Y2
M13190