Daikin FTXB50BV1B Service Manual page 34

Description
ANTIFREEZE PROTECTION OR HIGH PRESSURE CONTROL
Supposed Cause
1. Indoor air fi lter, heat exchanger block due to dust accumulation.
2. Indoor air short circuit.
3. Indoor coil thermistor faulty.
4. Indoor PCB faulty.
5. Fan blower dirty.
Troubleshooting
Check indoor air flow.
Any air short
circuit?
No
Check intake air filter.
Is it very dirty?
No
Check the dust
accumulate indoor coil.
Is it very dirty?
No
Check fan blower condition.
Is it very dirty?
No
Check indoor coil
thermistor resistance.
Does it conform
to the thermistor
resistance table?
No
Change indoor thermistor.
A5
Yes
Yes
Yes
Yes
# Refer to thermistor resistance table.(Page 60, 6.1)
Yes
Service Diagnosis
Provide sufficient air passage.
Clean the air filter.
Clean the indoor coil.
Clean fan blower.
Change indoor PCB.
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