High
Safety Shut-off on Ariston Eurocombi 20 1mfs

Your boiler has detected an internal electronic error and is preventing itself from igniting to ensure your safety.

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

Internal control failure detected by the P.C.B. at the start of every lighting phase.

From this model's manual
Verified against the Ariston Eurocombi 20 1mfs 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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