System Status, Fault And Lockout Led Codes - Lennox XC21 Series Unit Information

System Status, Fault and Lockout LED
Codes
LED codes are displayed using various LEDs located on
the air conditioner control (A175). See page 26 for location
of air conditioner control LEDs.
DS11 AND DS14 SYSTEM STATUS, FAULT AND
LOCKOUT LED CODES
DS11 (Green) and DS14
non−communicating mode diagnostics conditions that are
listed in table 9.
These LEDs display fault conditions in system cooling
capacity, dehumidification mode, anti−short cycle lockout,
high and low pressures, high discharge line temperature,
outdoor ambient temperature, and discharge sensor
failures.
DS15 AND DS13 COMPRESSOR FAULT AND
LOCKOUT LED CODES
DS15 (Yellow) and DS13
non−communicating mode diagnostics conditions that are
listed in table 10.
These LEDs display the most common fault conditions in
the system. When an abnormal condition is detected, this
function communicates the specific condition through
system diagnostic LEDs. The function is capable of
detecting both mechanical and electrical system problems.
Table 9. System Status, Fault and Lockout LED Codes and Related icomfort Toucht Thermostat Alert Codes
System fault and lockout LED (DS11 / DS14) alarm codes takes precedence over system status LED codes (cooling, heating stages or
defrost/dehumidification). Only the latest active LED fault or lockout alarm code if present will be displayed. If no fault or lockout codes are active, then
system status LEDs are routinely displayed. See notes 1 and 2 in table below for duration of fast / slow flashes and pause.
Air Conditioner
Control LEDs
Thermostat
DS11 DS14
Green Red
Off Off Not applicable
Simultaneous slow flash Not applicable
Alternating slow flash Not applicable
Simultaneous fast flash Critical Alert
Critical Alert
Alternating fast flash
XC21
(Red) LEDs indicate
(Red) LEDs indicate
icomfort
Toucht
Condition
Display
Power problem
Normal operation
5−minute
anti−short−cycle
delay
Moderate /
Ambient sensor
problem
Code 180
Moderate /
Coil sensor
problem
Code 417
IMPORTANT
DS15 and DS13 compressor LED fault and lockout
codes do not provide safety protection. The is a
monitoring function only and cannot control or shut down
other devices.
RESETTING LED FAULT AND LOCKOUT LED CODES
All LED fault and lockout codes can be reset manually or
automatically:
1. Manual Reset
Manual reset can be achieve by one of the following
methods:
S
Disconnecting R wire from the air conditioner
control's R terminal.
S
Turning the indoor unit off an on again.
Cycle the 24VAC power to air conditioner control off
and on. After power up, existing code will display for 60
seconds and then clear.
2. Automatic Reset
After a fault or lockout is detected, the air conditioner
control continues to monitor the unit's system and
compressor operations. When/if conditions return to
normal, the alert code is turned off automatically.
Possible
Cause(s)
SYSTEM STATUS
No power (24V)
1
Check control transformer power (24V).
to control
2
terminals R and
If power is available to control and LED(s) do not light,
C or control
replace control.
failure.
Unit operating Indicates that control has internal component failure. Cycle
normally or in 24 volt power to control. If code does not clear, replace
standby mode. control.
Initial power up,
safety trip, end of
None required (Jumper FIELD TEST pins to override)
room thermostat
demand.
Sensor being detected open or shorted or out of temperature range. control
will revert to time/temperature defrost operation. (System will still heat or cool).
This model does not utilize a coil sensor, however this alert indicates either an
open or shorted circuit. See if 10K resistor is not damage or missing. Resistor
is located in the sensor harness assembly, brown lead.
Page 36
Solution