High
30 50 70 on Chaffoteaux Serelia 24 MFFI

Your boiler is struggling to clear exhaust fumes correctly because it is not detecting the necessary air pressure change to safely start the heating process.

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

Extractor on and pressure regulator at rest

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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Related fault codes

30 60 70View →30 50 80View →

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