Lennox XP21 Series User Manual

Page 9
XP17
Table 2. Heat Pump Control (A175) Jumper and Terminal Descriptions
Board ID Label Description
E12 PSC Fan 240 VAC output connection for outdoor fan.
E16 PSC Fan 240 VAC input connection for outdoor fan.
E18
W 24VAC output for defrost auxiliary heat output.
L Thermostat service light connection.
Y2 24VAC thermostat input/output for second stage operation of the unit.
Y1 24VAC thermostat input for first stage operation of the unit.
O 24VAC thermostat input for reversing valve operation
DS Humiditrol Input
C 24VAC system common (Build -02 or later)
i-
Input/Output - RSBus data low. Used in communicating mode only with compatible indoor thermostat. (Build -02
or later)
i+
Input/Output - RSBus data high. Used in communicating mode only with compatible indoor thermostat. (Build
-02 or later)
R 24VAC system power input (Build -02 or later)
E19 and E20 O OUT 24 VAC output connection for reversing valve.
E21 and E22 LO-PS Connection for low-pressure switch (2.4 milliamps @ 18VAC)
E31 and E32 Y1 OUT 24 VAC common output, switched for enabling compressor contactor.
E24 and E25 HS-PS S87 connection for high-pressure switch (E25) and 24VAC (E24) to A177 “R” input.
E26 FAN 1 First Stage and second stage basic and precision dehumidification ECM fan motor 24VDC output connection 1.
E27 FAN 2 Second stage basic and precision dehumidification ECM fan motor 24VDC output connection 2.
E28 FAN C ECM common connection for ECM fan.
E30
Six position square pin header. P4 provides connections for the temperature sensors.
DIS
(YELLOW)
Not Used
AMB (BLACK)
AMB 1 — Outdoor ambient temperature sensor supply.
AMB 2 — Outdoor ambient temperature return.
Range is -40ºF to +140ºF
COIL
(BROWN)
COIL 1 — Outdoor coil temperature sensor supply.
COIL 2 — Outdoor coil temperature sensor return
E33 Field Test
This jumper allows service personnel to defeat the timed off control, initiate or terminate a defrost and field
programming of unit capacity feature.
E37
Comp Shift
Delay
The heat pump control has a field-selectable function to reduce occasional sounds that may occur while the unit
is cycling in and out of the defrost mode. When a jumper is installed on the DELAY pins (E37), the compressor
will be cycled off for 30 seconds going in and out of the defrost mode. Units are shipped with jumper installed on
DELAY pins. If no jumper is installed, the 30 second compressor shift delay is not active.
E47
50*
70
90
100
Seven position square pin header. E47 provides selection of the defrost terminate temperature based on the posi
tion of the selection jumper. The defrost termination temperature is measured by the defrost coil sensor. The
jumper termination pin is factory set at 50°F (10°C). If the temperature jumper is not installed, the default termina
tion temperature is 90°F (32°C). In addition, it provides selection points for enabling the field test mode.
W1 Short DS To R Cut for Humiditrol — Enhanced Dehumidification Accessory (EDA) applications.
* Factory default setting

Lennox XP21 Series Specifications

General

Brand	Lennox
Model	XP21 Series
Category	Heat Pump
Language	English