Error code
A1 Indoor-unit circuit-board fault
Applies to 2 models
FTXLS25K2V1B, FTXLS35K2V1B
What this means
The indoor unit's circuit board has detected a fault.
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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