Honeywell Heat/1Cool - T841A1563 Premier 2 Stage Thermostat User Manual page 112

WILLIAMSON
HEATING CHANGEOVER
Existing
Function
Terminals
Common
X
Power
R
Compressor
Y1
1st Stage
–
Heat
Aux. Heat
W2
Fan
G
C/O Valve
W1
Heat
C/O Valve
–
Cool
System Monitor/
L
System Defrost
Em. Heat
E
Multiple Aux.
Heat Loads
W3
LED Indication
–
2nd Stage
–
Compressor
2nd Stage
–
Cool
LED is energized when terminal is powered.
L terminal is powered continuously when thermostat is in Em. Ht. position.
Terminal is for multiple auxiliary heat loads such as contactors, sequencers,
or relays.
If multiple auxiliary heat loads are used, connect to W2 (Aux W8900B)
terminal.
70-6627 • 110
Electromechanical
X X X
R R R
Y Y1 Y Y1
– W1 W1
W2 W2 W2
G G G
B B B
O O O
L X1
E E E
W3 W3 W3
– X2 X2
– – –
– – –
TYPICAL THERMOSTATS AND SUBBASES — HONEYWELL MODEL NUMBER
T874N1008/Q674F1196
Electronic Replacement or Upgrade
®
Chronotherm
III
C C
R R
or
Y1 Y Y
W1 W1
W2 W2
G G
B B B
O O O
L L
E E
X1 X2 –
– –
– –
Terminal must be connected to the transformer common.
Do not remove factory-installed jumper.
Optional LED indication with completed circuit on X1 and X2 terminals.
Field-installed X2 to X (C) jumper.
Configure O/B (select models) in Installer Setup.
When W2 is not used, configure W2 cycle rate to NC.
Chronotherm
IV
C C C
R R R
Y1 Y Y1
W1 W1 W1
W2 W2 W2
G G G
or or
O/B B B O/B
or or
O/B O O O/B
L L L
E E E
– – X1 X2
– – –
– – –
C
R
Y1/W1
–
Aux.
G
O/B
O/B
L
E
–
W2
Y2
M13214