DAMA-SM-21-001
Troubleshooting
Service Diagnosis
60
Reference
Note
4.3 Freeze-up
Protection
Control
Error Code
A5
Method of Error
Detection
During cooling operation, the freeze-up protection control (operation halt) is activated according
to the temperature detected by the indoor heat exchanger thermistor.
High pressure control (heat pump model only).
During heating operations, the temperature detected by the indoor heat exchanger.
Thermistor is used for the high pressure control (stop, outdoor fan stop, etc.).
Error Decision
Conditions
During cooling operation, the indoor heat exchange temperature is below 0°C (32°F).
High pressure control
During heating operations, the temperature detected by the indoor heat exchanger thermistor is
above 61°C (141.8°F).
Supposed
Causes
Indoor Short-circuited air
Clogged air filter of the indoor unit
Dust accumulation on the indoor heat exchanger
Defective indoor heat exchanger thermistor
Defective indoor unit PCB
Troubleshooting
Check No.01
Refer to P.87
When replacing the defective thermistor(s), replace the thermistor as ASSY.
NO
NO
NO
Check No. 01
Check the indoor heat exchanger
thermistor.
YES
YES
YES
YES
NO
Provide sufficient air passage.
Clean the air filter.
Clean the indoor heat
exchanger.
Replace the indoor unit PCB
(control PCB).
Replace the indoor heat
exchanger thermistor.
As
described in the
thermistor characteristic
chart?
Check the air filter.
Check the dust accumulation on
the indoor heat exchanger.
Is there any short circuit?
Dirty?
Dirty?
Check the air passage.
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
Caution
Summary of Contents for FTK Series
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