Bosch A01 (5902)

Critical

Compress — Compressor motor overload (overcurrent).

Bosch A01 (5902): Compressor motor overload (overcurrent). This fault typically halts operation and needs immediate attention.

Possible causes

Overload / high pressure / stiff compressor.

Check steps

Check pressures, flow & compressor.
Measure winding resistance & insulation.

Affected parts

Verdichter
Inverter

Safety note

High voltage! Let capacitors discharge.

Source: Bosch/IVT/Buderus Compress Wärmepumpe Alarm-Tabelle (lvisawo.fi/jseducation.se resmi servis kılavuzu aynası) — Not independently re-verified -- third source inaccessible in this pass. Deferring to researcher's report.

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

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