Lennox iComfort S30 Installation And Setup Manual page 62

Table 1 Alert Codes and Troubleshooting
Applicable
Alert Priority
System
Code Condition
Component(s)
422 Moderate Outdoor unit
Moderate /
Inverter Controlled
423
Outdoor unit
Critical
424 Moderate Outdoor unit
425 Minor Outdoor unit
426 Critical Outdoor unit
Moderate / Inverter Controlled
427
Outdoor unit
Critical
Critical alerts are displayed on the Home screen, in the Homeowner alert button, and in the Installer alert button.
Minor and moderate alerts are found only in the Installer alert button.
Actual Displayed Alert
Component or System Operational State and Troubleshooting Tip
Text
Compressor top cap switch exceeding thermal limit.
√ Check condenser fan motor, TXV and indoor unit blower motor.
√ Check for stuck reversing valve or clogged refrigerant filter.
Compressor Top Cap
Switch Open √ XC/XP25: Check to ensure that one of the wires from the top cap switch has
not been disconnected from one of the TP terminals on the outdoor control.
Reconnect wire if disconnected.
√ Check superheat and sub-cooling.
The inverter has detected a circuit issue.
√ When this condition is detected the outdoor control will stop outdoor unit op­
erations and start the anti-short cycle timer – moderate condition.
OD Inverter CT Circuit
√ Outdoor control will lockout unit after 10 strikes within an hour – critical
Problem
condition.
√ Inverter LEDs will blink code 40
√ Refer to the unit service documentation for troubleshooting procedures.
The liquid line temperature sensor has malfunctioned.
√ In normal operation after outdoor control recognizes sensors, the alert code
will be sent if a valid temperature reading is lost.
√ Compare liquid line sensor resistance to temperature / resistance charts
in unit installation instructions.
OD Liquid Line Sensor
Faulty
√ Replace sensor pack if necessary.
√ At the beginning of (any) configuration, furnace or air handler control will
detect the presence of the sensor(s).
√ If detected (reading in range), appropriate feature will be set as 'installed'
and shown in the iComfort Wi-Fi
Outdoor control has increased minimum compressor speed to allow for
proper oil return due to low ambient temperature.
Compressor Speed
√ Outdoor ambient temperature is below system limit.
Limited by OD
Temperature
√ Control will attempt to run at lowest allowed compressor speed to allow for
proper oil return.
√ After ten faults within one hour outdoor control will lockout.
Excessive Inverter Alarms
√ Inverter alarms 12 to 14 and 53 do not count towards this lockout condition.
The inverter has detected a DC peak fault condition
√ If condition (55A or higher) is detected, outdoor unit will stop (compressor
and fan) – moderate condition.
√ Anti-short cycle is initiated.
OD Inverter DC Peak
√ If peak current (55A or higher) occurs 10 times within an hour, system will
Fault
lockout – critical condition.
√ Inverter LEDs will blink code 21.
√ Refer to the unit service documentation for detailed troubleshooting proce­
dures.
®
thermostat 'About' screen.
.
62
How to clear alert code
Automatically clears when error is
corrected.
A moderate alarm will clear auto­
matically when the inverter detects
the condition no longer exist and
will send a clear alarm message.
To clear critical alarm disconnect
power to outdoor unit and restart.
Automatically clears upon configu­
ration, or sensing normal values.
Automatically clears when outdoor
ambient temperature rises above
limit for more than five minutes.
To clear disconnect power to out­
door control and restart
To clear, disconnect and recon­
nect power to outdoor control.