Lennox XC21 - Page 24

Page 24
506518−01
Y1
O
R
W1
G
D
R
Y1
L
C
C
B
Y2
Y2
W
O
DS
L
T
T
W2
H
H
O
C
L
Y2
DS
DH
G
R
Y1
W2
W1
1
2
4
5
Furnace
ComfortSense[ 7000 Thermostats
Catalog # Y0349 or Y2081
XC21 Two−Stage Air
Conditioner A175
Control
On−board link
Low voltage thermostat
wiring
R connection required for outdoor unit with Air Conditioner A175 Control LSOM function. Resistor Kit (Cat# 47W97) is required when using
the ComfortSense 7000 (Y0349) with Air Conditioner A175 Control LSOMfeature. Resistor kit not required when using ComfortSense 7000
(Y2081).
Outdoor sensor for outdoor temperature display (Optional).
1
2
4
5
Cut Furnace Control on−board link W915 (clippable wire) for two−stage operation.
3
3
Cut loop jumper (clippable wire) for Humiditrol
®
application. This will slow the outdoor unit’s blower motor to 250
RPM. A wire must be installed between the DS terminals on the air handler and outdoor unit controls.
Cut on−board link (clippable wire) DS − R for Humiditrol
®
or Harmony III
TM
applications. This will slow the indoor blower motor to the
lowest speed. See furnace installation instruction or engineering handbook for lowest fan speed.
Figure 10. ComfortSense® 7000 Series Thermostat  Non−Communicating Connections −
Furnace/Two−Stage Air Conditioner