Lennox XC21 Series User Manual

Page 39
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
1 flash
then
pause
Off
Critical Alert
Code 401
Long run
time.
Compressor is
running extreme-
ly long run
cycles.
1
Low refrigerant charge.
2
Evaporator blower is not running.
S Check blower relay coil and contacts
S Check blower motor capacitor
S Check blower motor for failure or blockage
S Check evaporator blower wiring and
connectors
S Check indoor blower control
S Check thermostat wiring for open circuit
3
Evaporator coil is frozen.
S Check for low suction pressure
S Check for excessively low thermostat
setting
S Check evaporator airflow (coil blockages
or return air filter)
S Check ductwork or registers for blockage.
4
Faulty metering device.
S Check TXV bulb installation (size, location
and contact)
S Check if TXV/fixed orifice is stuck closed or
defective
5
Condenser coil is dirty
.
6
Liquid line restriction (filter drier blocked if
present)
.
7
Thermostat is malfunctioning
.
S Check thermostat sub−base or wiring for
short circuit
S Check thermostat installation (location and
level)
Clears the error
after 30
consecutive
normal run cycles,
or after power
reset.
2 flashes
then
pause
Off
Critical Alert
Code 402
System
pressure trip
Indicates the
compressor
protector is open
or missing supply
power to the
compressor.
1
High head pressure.
S Check high pressure switch if present in
system
S Check if system is overcharged with
refrigerant
S Check for non−condensable in system
2
Condenser coil poor air circulation (dirty,
blocked, damaged).
3
Condenser fan is not running.
S Check fan capacitor
S Check fan wiring and connectors
S Check fan motor for failure or blockage
4
Return air duct has substantial leakage.
Clears after four
consecutive
normal
compressor run
cycles, or after
power reset.
3 flashes
then
pause
Off
Moderate
Alert Code
403
Short cycling
Compressor is
running less than
three minutes.
1
Thermostat demand signal is intermittent.
2
Time delay relay or Air Conditioner Control is
defective.
3
If high pressure switch is present, see flash
Code 2 information.
Clears after four
consecutive
normal
compressor run
cycles, or after
power reset.
4 flashes
then
pause
Off
Critical Alert
Code 404
Locked rotor
Compressor has
a locked out due
to run capacitor
short, bearings
are seized,
excessive liquid
refrigerant.
1
Run capacitor has failed.
2
Low line voltage (contact utility if voltage at
disconnect is low).
S Check wiring connections
3
Excessive liquid refrigerant in the
compressor.
4
Compressor bearings are seized.
Clears after power
reset or four
normal
compressor
cycles.

Lennox XC21 Series Specifications

General

Brand	Lennox
Model	XC21 Series
Category	Air Conditioner
Language	English