77
Table 19. Alert Codes and Troubleshooting
GF= Gas Furnace, AH=Air Handler, ID=Indoor unit (GF or AH), HP=Heat Pump, AC=Air Conditioner, OD=Outdoor Unit (AC or HP), PA=Pure Air S, ZA=Zone system and TS=Thermostat
Alert
Code
Inverter
Flash
Code
Priority
Condition
Actual Displayed
Alert Text
Under dealer
control center >
Notifications
Component or System Operational State and Troubleshooting Tip
How to clear alert code
407
Service
Urgent
OD Compressor
Open Run
Circuit
The required amount of current is not passing through RUN current transformer.
Automatically clears after current is
sensed in RUN sensor, one normal
compressor run cycle, or after power
reset
408
Service
Urgent
OD Compressor
Contactor
Welded
The compressor is running continuously.
Automatically clears one normal
compressor run cycle or after power
reset.
409
Service Soon
OD Control
Board Low
24VAC
The secondary voltage for the applicable system component has fallen below 18VAC. This may
be due to:
•
Secondary voltage is below 18VAC.
• If this continues for 10 minutes, the thermostat will turn off the applicable system component.
Automatically clears after voltage is
detected as higher than 20VAC for
two seconds or after power reset.
410
Information
Only-Dealer
OD Open Low
Pressure Switch
Unit low pressure is below the required limit.
• Check operating pressures.
•
Low pressure switch opens at a specific pressure (system shuts down) and closes at a specific
pressure (system restarts).
Automatically clears when the
system detects that the issue no
longer exists.
411
Service
Urgent
OD Low
Pressure Switch
Strikes Lockout
The low pressure switch has opened five times during one cooling or heating demand.
• Thermostat will shut down the outdoor unit.
•
Open low pressure switch error count reached five strikes.
• Check system charge using both approach and sub-cooling methods.
•
Reset by putting outdoor unit control in test mode or resetting low voltage power.
Automatically clears when the
system detects that the issue no
longer exists.
412
Information
Only-Dealer
OD Open High
Pressure Switch
The unit high pressure is above the upper limit.
• System will shut down.
•
Confirm that the system is properly charged with refrigerant.
•
Check condenser fan motor, expansion valve (if installed), indoor unit blower motor, stuck
reversing valve or clogged refrigerant filter.
•
Confirm that the outdoor unit is clean.
Automatically clears after the high
pressure switch closes or a power
reset
413
Service
Urgent
OD High
Pressure Switch
Strikes Lockout
The high pressure switch has opened five times during one cooling demand.
• Thermostat will shut down the outdoor unit.
•
Open high pressure switch error count reached five strikes.
• Check system charge using superheat and sub-cooling temperatures.
• Check outdoor fan operation.
•
Check for dirt or debris blocking air flow to outdoor unit.
•
Reset by putting outdoor unit control in test mode or resetting low voltage power.
Automatically clears when the
system detects that the issue no
longer exists.
