Fujitsu Waterstage 6/1 fault code

What it means

Outdoor unit power supply abnormal

Outdoor unit power supply abnormal

UK models this code applies to

From the Fujitsu service literature we hold (Fujitsu Waterstage Super High Power D&T Manual, §Control System pp.03-3…03-5 — numeric display codes, interface-card LED pairs and outdoor-board flash counts with the published decode procedure) — not a scraped list.

Now the harder half: proving what caused it

6/1 names a symptom, not a root cause. In the app, the same code opens a guided investigation: what to measure first, the expected values for your exact model, and an honest verdict — including “nothing in this machine is broken” when that's what the readings say.