High
3 04 on Ariston Clas HE 24

Your boiler has locked itself out because the reset button has been pressed too many times in a short period, likely due to an underlying fault repeatedly cutting the system off.

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

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

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

5 01View →3 05View →

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