Error code

A5 High-pressure switch or frost protection

Fault

Daikin · FTX-K

Applies to 5 models
FTX20KV1B, FTX25KV1B, FTX35KV1B, FTX50KV1B, FTX60KV1B

What this means

A high-pressure protection device or indoor-unit frost-protection function has operated.

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 A5.