Error code
F90 Power Factor Correction (PFC) circuit protection
How it shows on the unit Timer LED blinks
Applies to 4 models
CS-LZ25TKE, CU-LZ25TKE, CS-LZ35TKE, CU-LZ35TKE
What this means
The outdoor Power Factor Correction (PFC) circuit detects abnormal DC voltage for the inverter power transistor.
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.
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