High
5 P1 on Ariston Clas HE 28

Your boiler tried to light the flame to heat your water but was unsuccessful on its first attempt.

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

1st Ignition Failed / FIRST IGNITION ATTEMPT UNSUCCESSFUL

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 P2View →5 P3View →

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