Emergency
5 0 2 on Ariston HS Premium

Your boiler has detected that a flame is present even though it has commanded the gas supply to shut off.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Detection of flame with gas valve closed

From this model's manual
Verified against the Ariston Hs Premium installation & service manual, page 21.
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 emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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