Lennox XC17 Series

Page 39
XC17
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 Flashes
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 cir-
cuit
3
Evaporator coil is frozen.
S Check for low suction pressure
S Check for excessively low thermostat
setting
S Check evaporator airflow (coil block-
ages or return air filter)
S Check ductwork or registers for block-
age.
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 (loca-
tion 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 block-
age
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 intermit-
tent.
2
Time delay relay or air conditioner con-
trol (A175) 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, ex-
cessive liquid re-
frigerant.
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 com-
pressor.
4
Compressor bearings are seized.
Clears after power reset
or four normal
compressor cycles.