Field Control Wiring - Lennox XP21 Series Installation Instructions Manual

Field Control Wiring

The following two illustrations provide examples on how to install control wiring using a non−communicating thermostat. For
examples of how to install control wiring in complete or partial communicating systems, see the icomfort Touch
Quick Start Guide which is provided with the thermostat.
HEAT PUMP
CONTROL (A175)
W
L
Y2
Y1
O
DS
2
C
7
R
1. Thermostat T terminals are used for outdoor sensor input. Use for thermostat's outdoor temperature display (optional).
2. R to L connection is required for this model when using the ComfortSense
required and ordered separately.
3. Air handler control ships from factory with metal jumpers installed across W1, W2 and W3. For one−stage electric heat, do not remove factory installed
metal jumpers.
4. Air handler control ships from factory with metal jumpers installed across W1, W2 and W3. For two−stage electric heat, remove factory installed metal
jumper between W1 to W2. Then connect thermostat wire between the air handler control's W2 and the thermostat's W2 terminal.
5. Cut on−board link (clippable wire) from R−O HEAT PUMP for heat pump applications.
6. Cut on−board link (clippable wire) from Y1−Y2 2 STAGE COMPR for two−stage compressor and two−speed fan operation.
7. Cut loop jumper (clippable wire) DS to R on two−stage units for Humiditrol
outdoor unit's fan speed to a specific RPM. A wire must be installed between the DS terminals on the furnace and outdoor unit controls. See table
15 for fan speed based on unit capacity.
8. Cut on−board link (clippable wire) DS−R for Humiditrol
slow the indoor blower motor to the lowest speed setting. See furnace installation instruction or engineering handbook for lowest fan speed
information.
Figure 17. ComfortSense® 7000 Series Thermostat
AIR HANDLER
CONTROL
DS
O
L
8
H
5
DH
R
C
Y1
6
Y2
G
W3
3
W2
4
W1
®
7000 − catalog number Y0349 only. Resistor Kit (catalog number 47W97)
®
whole−home dehumidication system applications. This will slow the
®
whole−home dehumidication system or Harmony IIIt zoning system applications. This will
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INDOOR
THERMOSTAT (S1)
R
G
W2
W1
O
L
H
D
B
Y2
Y1
C
T
T
Air Hander/Two−Stage Heat Pump
® thermostat
On−board link
Low voltage
thermostat wiring
Flat metal jumper
1
XP21 SERIES