High
153 on Baxi Suprima 30

Your boiler has experienced a glitch or a safety interruption and has been manually unlocked, but it may still require a full reset or professional inspection to clear the underlying issue.

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

Forced reset unit unlocked

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

E133View →E128View →E110View →

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