Lennox XC21 Series User Manual

Page 40
XC21
Air Conditioner
Control LEDs
Clearing Status
Solution
Possible
Cause(s)
Condition
icomfort
Toucht
Thermostat
Display
DS15
Yellow
Clearing Status
Solution
Possible
Cause(s)
Condition
icomfort
Toucht
Thermostat
Display
DS13
Red
5 flashes
then
pause
Off
Critical Alert
Code 405
Open circuit
Compressor has
an open circuit
due to power
disconnection,
fuse is open or
other similar
conditions.
1
Outdoor unit power disconnect is open.
2
Unit circuit breaker or fuse(s) is open.
3
Unit contactor has failed to close.
S Check compressor contactor wiring and
connectors
S Check for compressor contactor failure
(burned, pitted or open)
S Check wiring and connectors between
supply and compressor
S Check for low pilot voltage at compressor
contactor coil
4
High pressure switch is open and requires
manual reset.
5
Open circuit in compressor supply wiring or
connections.
6
Unusually long compressor protector reset
time due to extreme ambient temperature.
7
Compressor windings are damaged.
S Check compressor motor winding
resistance
Clears after one
normal
compressor run
cycle or power
reset.
6 flashes
then
pause
Off
Critical Alert
Code 406
Open start
circuit
Current not
sensed by Start
transformer.
1
Run capacitor has failed.
2
Open circuit in compressor start wiring or
connections.
S Check wiring and connectors between
supply and the compressor S terminal
3
Compressor start winding is damaged.
S Check compressor motor winding
resistance
Clears when
amperage is
detected in RUN
and START
sensors, or after
power reset.
7 flashes
then
pause
Off
Critical Alert
Code 407
Open run
circuit
Current not
sensed by run
transformer.
1
Open circuit in compressor start wiring or
connections.
S Check wiring and connectors between
supply and the compressor R terminal
2
Compressor start winding is damaged.
S Check compressor motor winding
resistance
Clears when
amperage is
detected in RUN
and START
sensors, or after
power reset.
8 flashes
then
pause
Off
Critical Alert
Code 408
Welded
contactor
Compressor
always runs
1
Compressor contactor failed to open.
2
Thermostat demand signal not connected to
module.
Clears after one
normal
compressor run
cycle or after
power reset.
9 flashes
then
pause
Off
Moderate/
Critical Alert
3
Code 409
Secondary
low voltage
24VAC is below
18VAC.
1
Control circuit transformer is overloaded.
2
Low line voltage (contact utility if voltage at
disconnect is low).
S Check wiring connections
Clears after
voltage is higher
than 20VAC for
two seconds, or
after power reset.
Fast simultaneous flashing of DS11,
DS13, DS14 and DS15
OEM mode Factory test mode.
1. Pause duration is two (2) seconds.
2. Fast flash duration is 1/2 second. Slow flash duration is one (1) second.
3. Initially a moderate status is displayed and is escalated to critical if alarm exists for more than 10 minutes.

Lennox XC21 Series Specifications

General

SEER Rating	Up to 21.00
Sound Rating	As low as 69 dB
Energy Star Certified	Yes
Refrigerant	R-410A
Cooling Capacity	2 to 5 tons
Warranty	10-year limited warranty on compressor and covered components