Lennox XC25-036-230-01 - Page 31

31
XC25
Table 6 continued
Alert
Codes
Inverter
Code
Inverter LED Flash
Code (number of
flashes)
Priority
Alarm Description Possible Causes and Clearing Alarm
Red LED Green LED
E 345
N/A
N/A N/A Critical
The O relay on the air-
handler or outdoor unit
has failed. Either the
pilot relay contacts did
not close or the relay
coil did not energize.
O relay / Sage 1 failed. Pilot relay contacts did not close or the relay
coil did not energize. Replace control. Fault clears after a power re
set.
E 409 N/A N/A N/A Moderate
Outdoor control sec
ondary voltage is
18VAC or less.
Secondary voltage is below 18VAC. After 10 minutes, operation is
discontinued. Check the indoor line voltage and transformer output
voltage. The alarm clears after the voltage is higher than 20VAC for
2 seconds or after a power reset.
E 410 N/A N/A N/A Moderate
The outdoor unit low
pressure switch has
closed.
Unit pressure is below the lower limit. The system is shutdown. The
low pressure switch opens at 25PSIG and closes at 40PSIG. Con
firm that the system is properly charged with refrigerant. Check
TXV, indoor unit blower motor, dirty filters or clogged refrigerant fil
ter. Confirm that the evaporator coil is clean. The alarm clears after
the pressure switch opens or after a power reset.
E 411 N/A N/A N/A Critical
The low pressure
switch has opened 5
times within one hour.
As a result, the out
door unit is locked out
.
Low pressure switch error count reached 5 strikes. The low pres
sure switch for HFC410A opens at 40PSIG and resets at 90PSIG.
Confirm that the system is properly charged with refrigerant. Check
for clogged TXV, blockage to indoor unit blower motor, dirty filters or
clogged refrigerant filter. Confirm that the evaporator coil is clean.
The alarm clears after a power reset.
E 412 N/A N/A N/A Moderate
The outdoor unit high
pressure switch has
opened.
Unit pressure is above the upper limit. System is shut down. The
high pressure switch opens at 590PSIG and closes at 418PSIG.
Confirm that the system is properly charged with refrigerant. Check
for clogged TXV, blockage to indoor unit blower motor, clogged refri
gerant filter. Confirm that the outdoor unit is clean. The alarm clears
after the pressure switch closes or a power reset.
For heating, indoor CFM may be set too low. For zoning system,
zone CFM may be set too low.
E 413 N/A N/A N/A Critical
The high pressure
switch has opened 5
times within one hour.
As a result, the out
door unit is locked out
.
Open high pressure switch error count reached 5 strikes. System is
shut down. The high pressure switch for HFC410A opens at
590PSIG and closes at 418PSIG. Confirm that the system is prop
erly charged with refrigerant. Check condenser fan motor, for
clogged TXV, for blockage to indoor unit blower motor, for stuck re
versing valve or clogged refrigerant filter. Confirm that the outdoor
unit is clean. The alarm clears after a power reset.
For heating, indoor CFM may be set too low. For zoning system,
zone CFM may be set too low.
E 416 N/A N/A N/A
Moderate
/ Critical
The outdoor coil
sensor has malfunc
tioned. As a result the
outdoor unit control will
not perform defrost.
Coil sensor being detected open or shorted, or temperature 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 tem
perature resistance chart. Replace coil sensor if needed. The
alarm clears when outdoor unit control detects proper coil sensor
readings or after a power reset.
E 422 N/A N/A N/A Moderate
Compressor top cap
switch exceeding
thermal limit.
Check condenser fan motor, TXV, indoor unit blower motor, stuck
reversing valve, clogged refrigerant filter or undercharge. When
error occurs with inverter slowdown errors, check for system over
charge. Automatically clears when error is corrected.
E 423 40 4 flashes OFF
Moderate
/ Critical
The inverter has de
tected a circuit prob
lem
.
Control locks out after 10 strikes within an hour. To clear, disconnect
power to outdoor unit and restart.
E 424 N/A N/A N/A Moderate
The liquid line tem
perature sensor has
malfunctioned.
In normal operation, after outdoor control recognizes sensors, the
alarm is sent if valid temperature reading is lost. Compare liquid line
sensor resistance to temperature/resistance charts in unit installation
instructions. Replace sensor pack if necessary. At the beginning of
(any) configuration, furnace or airhandler control detects the pres
ence of the sensor(s). If detected (reading in range), appropriate fea
ture is shown in the iComfort WiFi
®
thermostat About screen. The
alarm / fault clears upon configuration, or when normal values are
sensed.