Fault Codes / Bosch / H01 (5285)

Bosch H01 (5285)

High

Compress — Risk of frost in heating system.

Bosch H01 (5285): Risk of frost in heating system. This fault noticeably affects operation.

Possible causes

Heat sources active, pump PC0 running; low temperature.

Check steps

Check flow/pump PC0 & installer board fuse.
Check heat sources & frost protection.

Affected parts

Umwälzpumpe PC0

Safety note

Frost protection — do not leave unit powerless.

Source: Bosch resmi servis kılavuzu — Independently confirmed via web search: code 5285 = Risk of frost in heat system, triggers if T0/TC1/TC0 <5C for 10 minutes — matches 'Frostgefahr im Heizsystem'.

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

Look up in Enthalio →

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