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Hitachi 00100 fault code

Hitachi air conditioning

What the Hitachi 00100 fault code means, from the manufacturer's own service literature, and the UK models it applies to.

What it means

Refrigerant cycle fault (code 01)

Hitachi's broadest indoor indication — the refrigeration cycle is out of its expected envelope. Gauge before condemning anything; it is usually charge, a restriction or a metering issue, not the board.

Source: Hitachi Technical Catalogue §9.10 / §10.1.2 Error Code Information (RAK-PSES(W)/RAC-WSE — Hitachi UK; RAK-PED/RAC-WED — Hitachi R32 catalogue), both render-verified

UK models this code applies to

Tap yours to open 00100 on that machine.

Wall-mounted39
Cassettes28
Ducted21
Ceiling suspended7
Ceiling or floor8
Floor-standing8
Outdoor units60

00100 on these comes from each model's own manual, which may not match the meaning above — tap yours to read it.

Now the harder half: proving what caused it

00100 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.

Chase 00100 on your machine →

Free, no sign-up. Pick the model: where we hold a chart for it, it takes you through one question at a time.

Or watch one get chased — free demo →
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