Error code
H99 Indoor freeze protection
How it shows on the unit No Timer LED blinking; code stored in EEPROM
Applies to 4 models
CS-LZ25TKE, CU-LZ25TKE, CS-LZ35TKE, CU-LZ35TKE
What this means
Cooling or Soft Dry triggered indoor freeze protection, commonly associated with restricted airflow, low refrigerant, or a sensor/control problem. This is a stored protective code and may show no active alarm.
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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