Fault Codes / Bosch / A01 (5905)

Bosch A01 (5905)

High

Compress — Supply voltage below 180 VAC (undervoltage).

Bosch A01 (5905): Supply voltage below 180 VAC (undervoltage). This fault noticeably affects operation.

Possible causes

Mains undervoltage / weak supply.

Check steps

Measure supply voltage under load.
Check supply line/fuse/terminals.

Affected parts

Servicehandbuch — Fehlercode nachschlagen

Safety note

High voltage — caution.

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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