High
b43 on Remeha Quinta 30

The internal computer settings for your boiler have been altered, causing the system to stop working because it no longer knows how to run safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

One or several adjusted parameters out of range including some factory defaults which should not have been changed.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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