Page 33
31-5000751 Rev. 0
GF= Gas Furnace, AH=Air Handler, ID=Indoor unit (GF or AH), HP=Heat Pump, AC=Air Conditioner, OD=Outdoor Unit (AC or HP), ZA=Zone system and TS=Thermostat
Alert
Code
Inverter
Code
Inverter Flash
Code
Priority
Condition
Actual Displayed
Alert Text
Component or System Operational State
and Troubleshooting Tip
How to Clear
Alert Code
Red
LED
Green
LED
416
Service
Soon
OD Coil Sensor
Faulty
The outdoor coil sensor is either open, short-circuited or the temperature is
out of sensor range.
•
Outdoor unit control will not perform demand or time / temperature
defrost operation. (System will still heat or cool.)
•
This fault is detected by allowing the unit to run for 90 seconds before
checking sensor resistance. If the sensor resistance is not within range
after 90 seconds, the control will display a moderate code.
•
Advances from moderate to critical after ten (10) minutes.
•
Plug-in sensor harness correctly.
•
Check resistance of sensor to determine if it is open, shorted, out of
temperature calibration or out of ambient temperature range. Replace if
out-of-specifications.
Automatically clears
when outdoor unit
control detects
proper sensor
readings.
If sensor is faulty
and the system
is reporting the
condition as critical,
replaced sensor.
Reset power to clear
alert code.
422
Service
Soon
OD Compressor
Top Cap Switch
Open
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.
•
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.
Automatically
clears when error is
corrected.
423
40
4
flashes
OFF
Service
Soon/
Service
Urgent
OD Inverter CT
Circuit Fault
The inverter has detected a circuit issue.
•
When this condition is detected the outdoor control will stop outdoor unit
operations and start the anti-short cycle timer – moderate condition.
•
Outdoor control will lockout unit after 10 strikes within an hour – critical
condition.
•
Inverter LEDs will flash code 40
•
Refer to the unit service documentation for troubleshooting procedures.
Inverter flash code 40:
The sequence is:
Red LED: Four Flashes
Green LED: Off
NOTE:
Inverter normal operations with no error code present is as
follows. Red LED is ON and Green LED is OFF.
A moderate alert
code will clear
automatically when
the inverter detects
the condition no
longer exist and will
send a clear alert
code message.
To clear critical alert
code disconnect
power to outdoor unit
and restart.
424
Service
Soon
OD Liquid Line
Sensor Faulty
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.
•
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 thermostat ‘About’ screen.
Automatically clears
upon configuration,
or sensing normal
values.
426
Service
Urgent
OD Excessive
Inverter Alarms
After 10 faults within 60 consecutive minutes, the control will lockout.
Inverter will flash codes 12 to 14 and 53.
NOTE:
These inverter codes do not count towards this lockout condition.
To clear disconnect
power to outdoor
control and restart.
Table 12. Alert Codes and Troubleshooting