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Service Manual -
HRG18xxS1P
508206-01
Issue 2140
Page 77 of 83
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
434
53
5
flashes
3
flashes
Service Soon/
Service
Urgent
OD Inverter Comm
Error to Main
Control
• Outdoor control has lost communications with the inverter
continuously during a single thermostat call and one hour period.
• Outdoor control will stop all compressor demands – moderate
condition.
• Indoor blower will stop functioning.
NOTE:
Indoor blower will not run in test mode either when alert
code 434 is active. Only after system reset will it operate.
• This alert code will occur if the outdoor unit power is turned off
and the indoor unit power (24VAC to Comfort-Aire or Century
outdoor control) remains on, or if the indoor unit power is
turned off (24VAC to Comfort-Aire or Century outdoor control)
and the outdoor unit power is on. This could occur while
performing service or maintenance procedures on the indoor or
outdoor unit.
• The Comfort-Aire or Century outdoor control will attempt
to re-establish communication to the inverter when the alert
code 434 occurs by cycling the outdoor unit contactor off for
two minutes. Upon energizing the contactor the Comfort-Aire or
Century outdoor control will attempt to communicate to the inverter
for three minutes. This process will be repeated three times in
attempt to establish communication before locking out.
• If the unit is locked out with a critical alert code 434, reset the
system by cycling the outdoor unit power off and back on.
Then cycle the indoor power off (24VAC to the
Comfort-Aire or
Century
outdoor control) and then back on.
• If this condition continuously occurs during a one hour period
and during a single thermostat call, the outdoor unit will lock
out and display alert code 434 – critical condition.
Troubleshooting Options:
• Check for loose or disconnected electrical connections.
• Interruption of main power to inverter.
• Inverter LEDs will flash code 53.
• Refer to the unit service documentation for detailed troubleshooting
procedures.
Inverter flash code 53.
The sequence is:
•
Red LED: Five Flashes
•
Green LED: Three Flashes
NOTE:
Inverter normal operations with no error code present is as
follows. Red LED is ON and Green LED is OFF
Automatically clears
when the system
detects that the issue
no longer exists.
If the unit is locked
out with a critical
alert code 434, reset
the system by first
cycling the outdoor
unit power off and
back. Then cycle
the indoor power off
(24VAC to the
Comfort-Aire or
Century
outdoor
control) and then
back on.
435
60
6
flashes
OFF
Service
Urgent
OD Inverter
EEPROM
Checksum fault
Inverter internal error.
• When this error occurs, the outdoor control will cycle power to
the inverter by opening the contactor for two minutes – moderate
condition.
• Outdoor control will cycle power to the inverter three times and then
outdoor unit is locked out – critical condition.
• Inverter LEDs will flash code 60.
• Refer to the unit service documentation for detailed troubleshooting
procedures.
Inverter flash code 60.
The sequence is:
•
Red LED: Six 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.
To clear alert code
disconnect power
to outdoor unit and
restart.
Table 24. Outdoor Control 7-Segment Display Alert Codes and Inverter LED Flash Codes