Error code
H59 ECONAVI sensor abnormality
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 ECONAVI sensor is open, shorted, disconnected, or its PCB 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.
Using Claude Code or Meta Muse? Connect HeatPump AI and ask it about H59.