Fujitsu Waterstage A5 fault code
Fujitsu Waterstage heat pumps
What it means
Low pressure abnormal
Low pressure abnormal
UK models this code applies to
From the Fujitsu service literature we hold (Fujitsu Waterstage Comfort D&T Manual DA_CF001EF, §Control System pp.03-2…03-4 (official-distributor mirrors) — numeric display codes with Fujitsu's own reset and runs-despite-error columns, plus the interface-card LED table) — not a scraped list.
Waterstage Comfort 5 (WOYA060KLT + WSYA050ML3)Waterstage Comfort 6 (WOYA060KLT + WSYA080ML3)Waterstage Comfort WOYA080KLTWaterstage Comfort WOYA100KLTWaterstage Super High Power WOYG160LJL (1-phase)Waterstage Super High Power WOYK150LJL (3-phase)Waterstage Super High Power WOYK170LJL (3-phase)
Now the harder half: proving what caused it
A5 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.
Watch a code get chased — free demo →