Lennox XP25-024-230-01 Installation And Service Procedure page 32

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 416 N/A N/A
E 422 N/A N/A
E 423 40 4 flashes
E 424 N/A N/A
E 425 N/A N/A
E 426 N/A N/A
E 427 21 2 flashes
E 428 22 2 flashes
®
thermostat.
Priority
Green LED
The outdoor coil sensor has
Moderate malfunctioned. As a result
N/A
/ Critical
the outdoor unit control will
not perform defrost.
Compressor top cap switch
N/A Moderate
exceeding thermal limit.
Moderate The inverter has detected a
OFF
/ Critical circuit problem
The liquid line temperature
N/A Moderate
sensor has malfunctioned.
Outdoor
creased
pressor speed to allow for
proper oil return due to low
N/A Minor
ambient temperature. NOTE -
Minimum speed adjustments
begin at 45°F and increase to
100% minimum at 17°F.
N/A Critical Excessive inverter alarms
The inverter has detected a DC peak fault condition. If condition (55A or higher) is
detected, outdoor unit compressor and fan stop. Anti-short cycle is initiated. If peak
Moderate
1 flash current (55A or higher) occurs 10 times within an hour, system is locked out. Indicates
/ Critical
high pressure, condenser fan failure, locked compressor rotor or overcharge. To clear,
disconnect power to outdoor unit and restart.
The inverter has detected a
Moderate
2 flashes high main input current con­
/ Critical
dition
Alarm Description
Coil sensor being detected open or shorted, or temper­
ature is out of coil sensor range. Outdoor unit control
will not perform demand or time/temperature defrost
operation. System is still able heat and cool. Check the
resistance of the coil sensor and compare to temperat­
ure resistance chart. Replace coil sensor if needed.
The alarm clears when outdoor unit control detects
proper coil sensor readings or after a power reset.
Issue: One of the wires from the top cap switch had
pulled off one of the TP terminals on the outdoor con­
trol board.
Corrective Action: Reconnected wire onto top cap
terminal.
Control locks out after 10 strikes within an hour. To
clear, disconnect power to outdoor unit and restart.
.
In normal operation, after outdoor control recognizes
sensors, the alarm is sent if valid temperature reading
is lost. Compare liquid line sensor resistance to tem­
perature/resistance charts in unit installation instruc­
tions. Replace sensor pack if necessary. At the begin­
ning of (any) configuration, furnace or air­handler con­
trol detects the presence of the sensor(s). If detected
(reading in range), appropriate feature is shown in the
iComfort Wi­Fi
fault clears upon configuration, or when normal values
are sensed.
control has in­
minimum com­
Outdoor ambient temperature is below system limit.
Control attempts to run at lowest allowed compressor
speed to allow for proper oil return. Automatically
clears when outdoor ambient temperature rises above
limit for more than 5 minutes.
After ten faults within one hour, control is locked out,
indicating poor system operation. Review history of
alarms to resolve system setup. Check condenser fan
motor, TXV, indoor unit blower motor, over-charge, un­
dercharge, or clogged refrigerant filter.
To clear error, disconnect power to outdoor unit and
restart. Inverter alarms 12 to 14 and 53 do not count
toward this lock out condition.
If condition is detected, is detected, outdoor unit com­
pressor and fan stop. Anti­short cycle is initiated. If
condition occurs 5 times within an hour, system is
locked out.
Indicates high pressure, condenser fan failure or over­
.
charge.
To clear, disconnect power to outdoor unit and restart.
Page 32
Possible Causes and Clearing Alarm
®
thermostat About screen. The alarm /
XP25