High
Safety Shut-off on Ariston Euro Prisma 24

Your boiler has performed a self-diagnostic check and stopped working because it detected an internal error that requires a reset or professional inspection.

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.

What the manual says

Manufacturer manual

At the start of every lighting phase, the P.C.B. performs a series of internal controls. If a malfunction occurs, the boiler will shutdown until the problem has been resolved.

From this model's manual
Verified against the Ariston Euro Combi 30 Mffi installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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