Honeywell Heat/1Cool - T841A1563 Premier 2 Stage Thermostat User Manual page 89

Existing
Function
Terminals
Common
C
Power
R1
Night Setback
R2
Power
Compressor
Y
1st Stage
–
Heat
Aux. Heat
–
Fan
G
C/O Valve
B
Heat
C/O Valve
O
Cool
System Monitor/
X
System Defrost
Em. Heat
–
Multiple Aux.
Heat Loads
–
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 auxiliary heat loads such as contactors, sequencers,
or relays.
Disconnect external timimg device from circuit before wiring replacement
thermostat.
Optional LED indication activated with completed circuit on X1 and
X2 terminals.
Terminal must be connected to the transformer common.
TYPICAL THERMOSTATS AND SUBBASES — HONEYWELL MODEL NUMBER (CUSTOMER PART NUMBER)
T874G1378/Q674C1124
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
– – –
– – –
T874G1659/Q674C1330 (71115201)
USED WITH A NIGHT SETBACK THERMOSTAT
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 –
– –
– –
Do not remove factory-installed jumper.
Optional CHECK LED on T8611G1004. See Fig. 26.
Field-installed X2 to X (C) jumper.
C terminal is located on terminal strip, not on subbase.
If multiple auxiliary heat loads are used, connect to W2 (Aux W8900B)
terminal.
LED is energized when terminal is powered.
L terminal is powered continuously when thermostat is in Em. Ht. position.
MAMMOTH
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
– – –
– – –
T874H1096/Q674C1330 (71115201)
C
R
–
Y1/W1
–
Aux.
G
O/B O/B
O/B O/B
L
E
–
W2
Y2
M13195
70-6627 • 87