Bosch A01 (5523)

Critical

Compress — Short circuit in inverter (compressor control).

Bosch A01 (5523): Short circuit in inverter (compressor control). This fault typically halts operation and needs immediate attention.

Possible causes

Inverter/IGBT or compressor earth short.

Check steps

Power off: measure compressor insulation (megger) & inverter.

Affected parts

Inverter
Verdichter

Safety note

High voltage! Let capacitors discharge before work.

Source: Bosch/IVT/Buderus Compress Wärmepumpe Alarm-Tabelle (lvisawo.fi/jseducation.se resmi servis kılavuzu aynası) — Confirmed via direct PDF read p.24: code 5523, Installer, 'Warning Z1 Internal compressor driver warning 3', warning if incoming AC current >31A six times -- an overcurrent/internal inverter fault, no

Reviewed by Anıl Güzeldemir — in the refrigeration machine room since 2006, developer of Enthalio.

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