Error code
C9 Indoor room-temperature thermistor fault
Applies to 2 models
FTXTM30R2V1B, FTXTM40R2V1B
What this means
The indoor room-temperature thermistor has failed.
When to call a technician
This fault involves refrigerant, pressure, or electrical work that must be handled by a certified technician under EU F-gas rules. Do not attempt to open the refrigerant circuit, access mains wiring, or adjust pressure components yourself. Contact a qualified installer or servicer for this one.
See the official Daikin manualA deep link to the manufacturer's own PDF for full technical detail. We link to manuals, we never host them.
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