Error code
12 Wired-remote or server-room-control communication fault
How it shows on the unit OPERATION 1 blink, TIMER 2 blinks (each 0.5 s on/0.5 s off) while ECONOMY flashes rapidly (0.1 s on/0.1 s off)
Applies to 2 models
What this means
The unit reports a communication fault with a wired remote controller or a server-room controller.
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 Fujitsu manual (hosted by an authorized distributor)Hosted by an authorized distributor rather than by the manufacturer. We link to manuals, we never host them.
Using Claude Code or Meta Muse? Connect HeatPump AI and ask it about 12.