Hitachi 00601 fault code

What it means

The compressor/discharge overheat thermistor has seen too high a temperature — shortage of refrigerant, a restriction, or poor heat rejection driving discharge temperature up.

Safety: Discharge pipework runs very hot — allow to cool.

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 00601 on that machine.

00601 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

00601 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.

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

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