Lennox XC20-036-230-01 Installation And Service Procedure page 35

Table 6. Outdoor Control 7-Segment Display Alert Codes and Inverter LED Flash Codes
NOTE - System fault and lockout codes take precedence over system status codes (cooling, heating operating percentages or defrost/dehumidification).
Only the latest active fault or lockout codes are displayed (if present). If no fault or lockout codes are active, then system status codes are displayed. Alert
codes are also displayed on the iComfort Wi-Fi
Inverter LED Flash
Code (number of
Alert Inverter
flashes)
Code
Codes
Red LED
E 441 14 1 flash
E 442 N/A N/A
E 443 N/A N/A
E 600 N/A N/A
E 601 N/A N/A
®
thermostat.
Priority Alarm Description
Green LED
Compressor slowdown due
to high compressor current.
Compressor current is ap­
proaching limit. The com­
pressor speed automatic­
4 flashes Moderate ally slows. The control sets
indoor CFM and outdoor
RPM to values according to
demand percentage rather
than the actual Hz. Alarm is
automatically cleared..
The top cap switch has
opened five times within
N/A Critical
one hour. As a result, the
outdoor unit is locked out
Incorrect appliance
N/A Critical
size code selected.
Compressor
N/A Critical cycled OFF on utility load
shedding.
Outdoor unit has been
N/A Critical cycled OFF on low temper­
ature protection.
Possible Causes and Clearing Alarm
Issue: Possible issue is system running at high pres­
sures. Check for high pressure trips or other alert codes in
room thermostat and outdoor control.
When compressor thermal protection sensor opens five
times within one hour, outdoor stops working. To clear,
disconnect power to outdoor unit and restart.
.
Check for proper configuring of unit size codes for out­
door unit in configuration guide or in installation instruc­
tions. If replacing inverter, verify inverter model matches
unit
unit size. The alarm/fault clears after the correct match is
detected following a reset. Remove the thermostat from
the system while applying power and reprogramming.
Load shedding function: Provides a method for a local
has been
utility company to limit the maximum power level usage of
the outdoor unit. The feature is activated by applying 24
volts AC power to the L and C terminals on the outdoor
control.
Low temperature protection: Outdoor unit will not operate
when the outdoor temperature is at or below
(­20°C). If the unit is operating and the outdoor temper­
ature drops below ­4°F (­20°C), the unit continues to op­
erate until the room thermostat is satisfied or the outdoor
temperature drops to ­15°F (­26°C). Outdoor unit ambi­
ent sensor provides temperature readings.
35
­4°F
XC20