Medium
3 04 on Ariston Clas HE Evo

Your boiler has detected that you have attempted to restart it too many times in a short window, which has caused the internal computer to lock itself out for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Too many (> 5) resets in 15 minutes Main P.C.B. error

From this model's manual
Verified against the Ariston Clas He 35 System installation & service manual, page 38.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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