Lennox XP17-024-230-01 Installation And Service Procedure page 17

Heat Pump Control
iComfortt iComfortt
LEDs
-enabled -enabled
Thermostat Thermostat
DS15 DS13
Yellow Red Display Display
1 flash
Critical Alert
then Off
Code 401
pause
2 flashes
Critical Alert
then
Off
Code 402
pause
3 flashes Moderate
then Off Alert Code
pause 403
4 flashes
Critical Alert
then Off
Code 404
pause
XP17
Possible Possible
Condition Condition
Cause(s) Cause(s)
Compressor is
Long run
running extreme­
time. ly long run
cycles.
Indicates the
compressor
System
protector is open
pressure trip or missing supply
power to the
compressor.
Compressor is
Short cycling running less than
three minutes.
Compressor has
a locked out due
to run capacitor
Locked rotor short, bearings
are seized,
excessive liquid
refrigerant.
Page 17
Solution Solution
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 connec­
tors
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 re­
turn 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 de­
fective
5 .
Condenser coil is dirty
6
Liquid line restriction (filter drier blocked if pres­
.
ent)
7
Thermostat is malfunctioning
S
Check thermostat sub-base or wiring for short
circuit
S
Check thermostat installation (location and
level)
1
High head pressure.
S
Check high pressure switch if present in sys­
tem
S
Check if system is overcharged with refriger­
ant
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.
1
Thermostat demand signal is intermittent.
2
Time delay relay or heat pump control is defec­
tive.
3
If high pressure switch is present, see flash code
2 information.
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.
Clearing Sta­ Clearing Sta­
tus tus
Clears the error
after 30 consec­
utive normal run
cycles, or after
power reset.
.
Clears after four
consecutive
normal com­
pressor run
cycles, or after
power reset.
Clears after four
consecutive
normal com­
pressor run
cycles, or after
power reset.
Clears after
power reset or
four normal
compressor
cycles.