Honeywell Heat/1Cool - T841A1563 Premier 2 Stage Thermostat User Manual page 95

Existing
Function
Terminals
Common
X
Power
R
Compressor
Y
1st Stage
–
Heat
Aux. Heat
W2
Fan
G
C/O Valve
–
Heat
C/O Valve
O
Cool
System Monitor/
L
System Defrost
Outdoor
W3
Thermistor/
Sensor
Em. Heat
E
LED Indication
–
2nd Stage
–
Compressor
2nd Stage
–
Cool
Terminal must be connected to the transformer common.
Tape off. Thermostat replaces outdoor reset with improved zero droop
performance.
Do not remove factory-installed jumper.
Optional LED indication with completed circuit on X1 and X2 terminals.
Electromechanical
B B B
R R R
Y Y Y
– – –
W W W
G G G
– – –
O O O
F F F
T T T
X2 X2 X2
– – –
– – –
– – –
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 –
– –
– –
Configure O/B (select models) in Installer Setup.
Replace existing thermistor with Honeywell C815A1005.
When W2 is not used, configure W2 cycle rate to NC.
LED is energized when terminal is powered.
L terminal is powered continuously when thermostat is in Em. Ht. position.
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
– – –
– – –
SECO
TA2060
C
R
Y1/W1
–
Aux.
G
O/B O/B
O/B O/B
L
E
X2 –
W2
Y2
M13199
70-6627 • 93