Lennox EL23XCV Series Manual page 38

TABLE 7. 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/dehumidifi-
cation). 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 S30/S40 thermostat.
Inverter LED Flash Code
Alert Inverter
(number of flashes)
Codes Code
Red LED
E433 29 2 flashes
E434 53 5 flashes
E435 60 6 flashes
E436 62 6 flashes
E437 65 6 flashes
Priority
Green LED
The inverter has detected
Moderate
9 flashes a compressor over-current
/ Critical
condition.
Outdoor control has lost
communications with the
inverter for greater than 3
minutes. Outdoor unit will
stop all compressor demand.
Outdoor control will attempt
Moderate to establish communication
3 flashes
/ Critical multiple times and will
automatically clear when
the error clears. Unit will
lock out after 60 minutes
if communication is not
established and will display a
critical error code.
Moderate
OFF Inverter internal error
/ Critical
Inverter heat sink temperature
exceeded limit. Occurs when
the heat sink temperature
exceeds the inverter limit.
Inverter issues code 13 first,
then slows down to allow the
heat sink to cool. If temperature
remains high, outdoor unit stops
(compressor and fan). Anti-short
cycle is initiated. If condition
Moderate
2 flashes
occurs 5 times within an hour,
/ Critical
system is locked out.
To clear, disconnect power to
the indoor unit (24VAC power
source to the outdoor control)
which will power off the outdoor
control and will open the
outdoor unit contactor, which
interrupts power to the inverter
and then re-apply power.
Heat sink temperature sensor
fault has occurred (temperature
Moderate
5 flashes less than 4ºF or greater than
/ Critical
264ºF after 10 minutes of
operation).
Alarm Description
Error occurs when compressor peak phase current is greater than
28A. Inverter issues code 14 first and slows down to try to reduce
the current. If the current remains high, outdoor unit compressor
and fan stop. Anti-short cycle is initiated. If condition occurs five
times within an hour, system is locked out.
To clear, disconnect power to the indoor unit (24VAC power source
to the outdoor control) which will power off the outdoor control and
will open the outdoor unit contactor, which interrupts power to the
inverter and then re-apply power.
Issues:
(1) Outdoor disconnect is off or outdoor power is off, when indoor
power is on (source for 24VAC)
(2) Loose electrical power connections
(3) interruption of main power to the inverter
(4) Generator powers indoor unit, but not the outdoor unit.
Corrective Actions:
(1) To reset, cycle the indoor power off (source of 24VAC to
outdoor unit) and back on. This will de-energize outdoor control
and inverter by cycling the contactor.
(2) Make sure the disconnect is on
(3) check electrical power supply connections
(4) Check for proper main 230V power supply
When this error occurs, the outdoor control cycles power to the
inverter by opening the contactor for two minutes.
Check that the EEPROM is properly seated. After power is cycled
to the inverter 3 times, the outdoor unit is locked out.
If problem persists, replace the inverter.
Issue:
This error may occur if the outdoor fan fails to operate or the
inverter heat sink is obstructed with debris.
Feedback from supplier tear down of inverter indicates that the
screws that hold the inverter to the inverter board were loose
causing poor contact between these two components.
Corrective Action:
Tighten screws that hold the heat sink to the inverter control
board.
NOTE: Wait five minutes to allow capacitor to discharge before
checking screws.
Occurs when the temperature sensor detects a temperature less
than 0.4ºF or greater than 264ºF after 10 minutes of operation. If
condition is detected, outdoor unit will stop (compressor and fan).
Anti-short cycle is initiated. If condition occurs 5 times within an
hour, system will lock out.
To clear, disconnect power to the indoor unit (24VAC power source
to the outdoor control) which will power off the outdoor control and
will open the outdoor unit contactor, which interrupts power to the
inverter and then re-apply power.
If problem persists, replace inverter.
Page 38
Possible Causes and Clearing Alarm